{"id":"CVE-2024-9312","aliases":["EUVD-2024-2934","GHSA-4gfw-wf7c-w6g2","GO-2024-3188","SUSE-SU-2024:3911-1","SUSE-SU-2025:0429-1","openSUSE-SU-2024:0350-1","openSUSE-SU-2024:14447-1"],"status":"published","title":"Authd allows attacker-controlled usernames to yield controllable UIDs","description":"Authd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00281,"percentile":0.20773,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-286","CWE-335"],"published":"2024-10-10T13:42:31Z","modified":"2026-10-28T02:30:23Z","fixes":[{"ecosystem":"Go","package":"github.com/ubuntu/authd","fixed_in":["0.3.6"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"github.com/ubuntu/authd","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.0.0-20230706090440-d8cb2d561419"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/ubuntu/authd","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"last_affected":"0.0.0-20230706090440-d8cb2d561419"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/ubuntu/authd","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.3.6"}]}]},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Module for Package Hub 15 SP5","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20241030T212825-150000.1.9.1"}]}],"bundled":44},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Module for Package Hub 15 SP6","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20241030T212825-150000.1.9.1"}]}],"bundled":44},{"source":"osv","ecosystem":"openSUSE:Leap 15.5","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20241030T212825-150000.1.9.1"}]}],"bundled":44},{"source":"osv","ecosystem":"openSUSE:Leap 15.6","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20241030T212825-150000.1.9.1"}]}],"bundled":44},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Module for Package Hub 15 SP6","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20250207T224745-150000.1.32.1"}]}],"bundled":28},{"source":"osv","ecosystem":"openSUSE:Leap 15.6","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20250207T224745-150000.1.32.1"}]}],"bundled":28},{"source":"osv","ecosystem":"SUSE:Package Hub 12","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20241104T154416-5.1"}]}],"bundled":56},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"govulncheck-vulndb","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.0.20241030T212825-1.1"}]}],"bundled":44}],"products":[{"vendor":"canonical","product":"authd"},{"vendor":"canonical ltd.","product":"authd"},{"vendor":"ubuntu","product":"authd"}],"references":[{"url":"https://github.com/ubuntu/authd/security/advisories/GHSA-4gfw-wf7c-w6g2","tags":["issue-tracking","Exploit","Mitigation","Vendor Advisory","report","web","advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2024-9312","tags":["issue-tracking","Third Party Advisory","report","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2024-9312","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-4gfw-wf7c-w6g2"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/9xxx/CVE-2024-9312.json","tags":["advisory"]},{"url":"https://github.com/ubuntu/authd","tags":["package"]},{"url":"https://www.suse.com/support/update/announcement/2024/suse-su-20243911-1/","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2022-45157","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2023-22644","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2023-32197","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10214","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10241","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-22030","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-22036","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-33662","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-36814","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-38365","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-39223","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47003","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47067","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47182","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47534","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47616","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47825","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47827","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47832","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47877","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-48909","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-48921","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-49380","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-49381","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-49753","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-49757","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-50312","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-7558","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-7594","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-8037","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-8038","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-8901","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-8975","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-8996","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9180","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9264","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9312","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9313","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9341","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9355","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9407","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9486","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9594","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-9675","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2025/suse-su-20250429-1/","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2022-47930","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10846","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-11741","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-13484","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-35177","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-3727","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-45336","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-45339","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-45340","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-45341","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47770","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-50354","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-0750","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-22865","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-22866","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-22867","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-23216","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24366","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24369","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24371","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24376","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24784","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24786","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24787","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24883","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2025-24884","tags":["web"]},{"url":"https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/thread/3GBL6IN35EDC2YQIKBPTX7XQQ67KRPAM/","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2024-0132","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-0133","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10005","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10006","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10086","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-10452","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-39720","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-46872","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-47401","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-50052","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2024-8185","tags":["web"]},{"url":"https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/thread/XTEQAM75LF5DZCFX3MOH4IT3DWP5ZTL6/","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2024-9312","description":"Authd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.","status":"published","published":"2024-10-10T13:42:31.95Z","modified":"2024-10-10T14:55:40.228Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-286"],"updated_at":"2026-11-02T14:34:06.147811Z"}],"euvd":[{"id":"EUVD-2024-2934","description":"Authd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.","status":"published","published":"2024-10-10T13:42:31Z","modified":"2024-10-10T14:55:40Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-03T00:27:41.519615Z"}],"ghsa":[{"id":"GHSA-4gfw-wf7c-w6g2","title":"Authd allows attacker-controlled usernames to yield controllable UIDs","description":"CVE description:\n\nAuthd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.\n\n\n----- original report -----\n# Cause\nauthd assigns user IDs as a pure function of the user name. Moreover, the set of UIDs is much too small for pseudo-random assignment to work: the birthday bound predicts random collisions will occur with probability 50% after only 54 562 IDs were assigned.\n\n`authd` only checks for uniqueness [within its local cache](https://github.com/ubuntu/authd/blob/4946962aa4ac6e5b7d2b53503026659581c73907/internal/users/cache/update.go#L67-L71), which\n- may be inconsistent across multiple systems within the same domain ;\n- may be purged, due to being stored in `/var/cache` ;\n- automatically removes entries of users who have not logged into that specific system within the last 6 months.\n\nThe current `GenerateID` method, authored in September 2024 (commit a6c85ed24b8d17a2d11c859e8d70f5a52fa69690),\nrepeatedly hashes the user name until the 4 leading bytes fall into the interval [60 000; 2³¹[ :\nhttps://github.com/ubuntu/authd/blob/f9f851540e6377fca18a45ce7a02d024c1dbd6e9/internal/users/manager.go#L425\nhttps://github.com/ubuntu/authd/blob/f9f851540e6377fca18a45ce7a02d024c1dbd6e9/internal/services/nss/nss.go#L188\n\nPrevious versions are affected by similar issues, though without the use of a cryptographic hash in `GenerateID`, making exploitation computationally-easier.\n\n\n# Impact\n\nSince GenerateID is a pure function with no secret input, and the set of UIDs is small, an adversary which can register users with chosen names can\n- register multiple users with colliding IDs, or\n- register a single user whose ID collides with a target user's, whether one managed by `authd`, or a system user whose well-known ID is in a range which [overlaps `authd`'s].\n\nIn the latter case, as all access control performed by the Linux kernel (and other Unices' kernels) is based on IDs and not usernames, if the attacker can sign into a system, they will have the same privileges as the target user.  The attacker can bypass the uniqueness check in (at least) the following ways:\n- engineer a situation where the system administrator purges `/var/cache` ;\n- target a system account [whose UID is in `authd`'s range](https://github.com/ubuntu/authd/issues/547) ;\n- target an account which hasn't logged into a specific system in more than 6 months.\n  Note that this isn't limited to inactive accounts *within the entire domain*, and impersonation on a given system can potentially be leveraged to compromise the target account on other systems; for example:\n  - user `alice` is known to log into `1.example.com` ;\n  - the attacker computes a preimage (a username which yields the same UID), let's call it `bob` ;\n  - the attacker creates the account `bob` and logs into `2.example.com`, succeeding if alice hasn't (recently) logged into that system ;\n  - the attacker can now manipulate resources exposed on `2` as if they were alice; assuming `/home` is shared, they could manipulate `~alice/.ssh/authorized_keys`, `~alice/.config`, alice's shell's initialization file, etc.\n    Note: NFSv4's `idmap` mechanism may prevent this, but isn't enabled by default (unless Kerberos is used, which isn't the case in an `authd` deployment)\n  - at that point, gaining code execution as alice on `1.example.com` is usually trivial.\n\nSince the necessary computation can be performed entirely offline, this wouldn't be affected by any rate-limits, and the only audit trail would be a single user registration. This would require on average less than 2³¹ computations of `GenerateID`: assuming SHA-256's cost is 25 cycles-per-byte, a clock speed of 3GHz, and short (≤32B) generated usernames, this is less than 10 minutes of a single core's time.\n\n[overlaps `authd`'s]: https://github.com/ubuntu/authd/issues/547\n\n# Remediation\n\nThe simplest and likely-best remediation path would be for the external IdP to provide a guaranteed-unique user ID in the correct range.\nIn OIDC, this is commonly communicated through a claim, though its name would need to be configurable as there's no real standard:\n- CERN uses `cern_person_id`: https://auth.docs.cern.ch/user-documentation/oidc/config/ ;\n- Okta, Zitadel, and many other IdPs, require the realm's administrator to define a custom attribute, conventionally called `uid` or `uidNumber` ;\n- etc.\n\nThis is also supported by other commonplace identity providers, such as LDAP and Active Directory:\nhttps://learn.microsoft.com/en-us/windows/win32/adschema/a-uidNumber\n\nMS Entra presumably supports this as well.\n\n\nIf that is not possible for some reason, architectural changes to authd would likely be required:\nassigning user IDs from a small space (such as Linux's 32b UIDs) requires mutable state to ensure uniqueness, whereas authd's design currently assumes no mutable state is held, aside from some transient, local cache.\nMoreover, that mutable state may need to be synchronised across multiple machines as uniform UIDs are often necessary, for instance when accessing a common networked filesystem.\n\n\n# Acknowledgements\n\nThanks to Michael Gebetsroither for assisting with the writeup, and Jamie Bliss for the same as well as investigating when the issue was introduced in authd.","status":"published","published":"2024-10-10T16:43:58Z","modified":"2024-10-11T02:30:30Z","cvss":[{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H","level":"medium"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-286"],"updated_at":"2026-11-02T14:38:09.785133Z"}],"nvd":[{"id":"CVE-2024-9312","description":"Authd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.","status":"published","published":"2024-10-10T14:15:05.863Z","modified":"2026-06-17T08:24:20.137Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":6.4,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-286","CWE-335"],"updated_at":"2026-11-02T14:10:31.271525Z"}],"osv":[{"id":"CVE-2024-9312","description":"Authd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.","status":"published","published":"2024-10-10T13:42:31.95Z","modified":"2026-10-28T02:30:23.965190197Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-286"],"updated_at":"2026-11-02T15:44:45.712478Z"},{"id":"GHSA-4gfw-wf7c-w6g2","title":"Authd allows attacker-controlled usernames to yield controllable UIDs","description":"CVE description:\n\nAuthd, through version 0.3.6, did not sufficiently randomize user IDs to prevent collisions. A local attacker who can register user names could spoof another user's ID and gain their privileges.\n\n\n----- original report -----\n# Cause\nauthd assigns user IDs as a pure function of the user name. Moreover, the set of UIDs is much too small for pseudo-random assignment to work: the birthday bound predicts random collisions will occur with probability 50% after only 54 562 IDs were assigned.\n\n`authd` only checks for uniqueness [within its local cache](https://github.com/ubuntu/authd/blob/4946962aa4ac6e5b7d2b53503026659581c73907/internal/users/cache/update.go#L67-L71), which\n- may be inconsistent across multiple systems within the same domain ;\n- may be purged, due to being stored in `/var/cache` ;\n- automatically removes entries of users who have not logged into that specific system within the last 6 months.\n\nThe current `GenerateID` method, authored in September 2024 (commit a6c85ed24b8d17a2d11c859e8d70f5a52fa69690),\nrepeatedly hashes the user name until the 4 leading bytes fall into the interval [60 000; 2³¹[ :\nhttps://github.com/ubuntu/authd/blob/f9f851540e6377fca18a45ce7a02d024c1dbd6e9/internal/users/manager.go#L425\nhttps://github.com/ubuntu/authd/blob/f9f851540e6377fca18a45ce7a02d024c1dbd6e9/internal/services/nss/nss.go#L188\n\nPrevious versions are affected by similar issues, though without the use of a cryptographic hash in `GenerateID`, making exploitation computationally-easier.\n\n\n# Impact\n\nSince GenerateID is a pure function with no secret input, and the set of UIDs is small, an adversary which can register users with chosen names can\n- register multiple users with colliding IDs, or\n- register a single user whose ID collides with a target user's, whether one managed by `authd`, or a system user whose well-known ID is in a range which [overlaps `authd`'s].\n\nIn the latter case, as all access control performed by the Linux kernel (and other Unices' kernels) is based on IDs and not usernames, if the attacker can sign into a system, they will have the same privileges as the target user.  The attacker can bypass the uniqueness check in (at least) the following ways:\n- engineer a situation where the system administrator purges `/var/cache` ;\n- target a system account [whose UID is in `authd`'s range](https://github.com/ubuntu/authd/issues/547) ;\n- target an account which hasn't logged into a specific system in more than 6 months.\n  Note that this isn't limited to inactive accounts *within the entire domain*, and impersonation on a given system can potentially be leveraged to compromise the target account on other systems; for example:\n  - user `alice` is known to log into `1.example.com` ;\n  - the attacker computes a preimage (a username which yields the same UID), let's call it `bob` ;\n  - the attacker creates the account `bob` and logs into `2.example.com`, succeeding if alice hasn't (recently) logged into that system ;\n  - the attacker can now manipulate resources exposed on `2` as if they were alice; assuming `/home` is shared, they could manipulate `~alice/.ssh/authorized_keys`, `~alice/.config`, alice's shell's initialization file, etc.\n    Note: NFSv4's `idmap` mechanism may prevent this, but isn't enabled by default (unless Kerberos is used, which isn't the case in an `authd` deployment)\n  - at that point, gaining code execution as alice on `1.example.com` is usually trivial.\n\nSince the necessary computation can be performed entirely offline, this wouldn't be affected by any rate-limits, and the only audit trail would be a single user registration. This would require on average less than 2³¹ computations of `GenerateID`: assuming SHA-256's cost is 25 cycles-per-byte, a clock speed of 3GHz, and short (≤32B) generated usernames, this is less than 10 minutes of a single core's time.\n\n[overlaps `authd`'s]: https://github.com/ubuntu/authd/issues/547\n\n# Remediation\n\nThe simplest and likely-best remediation path would be for the external IdP to provide a guaranteed-unique user ID in the correct range.\nIn OIDC, this is commonly communicated through a claim, though its name would need to be configurable as there's no real standard:\n- CERN uses `cern_person_id`: https://auth.docs.cern.ch/user-documentation/oidc/config/ ;\n- Okta, Zitadel, and many other IdPs, require the realm's administrator to define a custom attribute, conventionally called `uid` or `uidNumber` ;\n- etc.\n\nThis is also supported by other commonplace identity providers, such as LDAP and Active Directory:\nhttps://learn.microsoft.com/en-us/windows/win32/adschema/a-uidNumber\n\nMS Entra presumably supports this as well.\n\n\nIf that is not possible for some reason, architectural changes to authd would likely be required:\nassigning user IDs from a small space (such as Linux's 32b UIDs) requires mutable state to ensure uniqueness, whereas authd's design currently assumes no mutable state is held, aside from some transient, local cache.\nMoreover, that mutable state may need to be synchronised across multiple machines as uniform UIDs are often necessary, for instance when accessing a common networked filesystem.\n\n\n# Acknowledgements\n\nThanks to Michael Gebetsroither for assisting with the writeup, and Jamie Bliss for the same as well as investigating when the issue was introduced in authd.","status":"published","published":"2024-10-10T16:43:58Z","modified":"2024-10-11T14:57:12.42287Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H","level":"high"},{"version":"4.0","score":5.5,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H","level":"medium"}],"cwes":["CWE-286"],"updated_at":"2026-11-02T15:46:37.148947Z"},{"id":"GO-2024-3188","title":"Authd allows attacker-controlled usernames to yield controllable UIDs in github.com/ubuntu/authd","description":"Authd allows attacker-controlled usernames to yield controllable UIDs in github.com/ubuntu/authd","status":"published","published":"2024-10-11T14:32:39Z","modified":"2026-03-03T04:55:53.483333Z","updated_at":"2026-11-02T15:47:01.453823Z"},{"id":"openSUSE-SU-2024:0350-1","title":"Security update for govulncheck-vulndb","description":"This update for govulncheck-vulndb fixes the following issues:\n\n- Update to version 0.0.20241104T154416 2024-11-04T15:44:16Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3233 CVE-2024-46872 GHSA-762g-9p7f-mrww\n  * GO-2024-3234 CVE-2024-47401 GHSA-762v-rq7q-ff97\n  * GO-2024-3235 CVE-2024-50052 GHSA-g376-m3h3-mj4r\n  * GO-2024-3237 CVE-2024-0133 GHSA-f748-7hpg-88ch\n  * GO-2024-3239 CVE-2024-0132 GHSA-mjjw-553x-87pq\n  * GO-2024-3240 CVE-2024-10452 GHSA-66c4-2g2v-54qw\n  * GO-2024-3241 CVE-2024-10006 GHSA-5c4w-8hhh-3c3h\n  * GO-2024-3242 CVE-2024-10086 GHSA-99wr-c2px-grmh\n  * GO-2024-3243 CVE-2024-10005 GHSA-chgm-7r52-whjj\n\n- Update to version 0.0.20241101T215616 2024-11-01T21:56:16Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3244 CVE-2024-50354 GHSA-cph5-3pgr-c82g\n  * GO-2024-3245 CVE-2024-39720\n  * GO-2024-3246 CVE-2024-8185 GHSA-g233-2p4r-3q7v\n\n- Update to version 0.0.20241030T212825 2024-10-30T21:28:25Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3230 CVE-2024-48921 GHSA-qjvc-p88j-j9rm\n  * GO-2024-3232 CVE-2024-10241 GHSA-6mvp-gh77-7vwh\n\n- Update to version 0.0.20241030T160108 2024-10-30T16:01:08Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3226 CVE-2024-47827 GHSA-ghjw-32xw-ffwr\n  * GO-2024-3227 CVE-2024-10214 GHSA-hm57-h27x-599c\n  * GO-2024-3228 GHSA-wcx9-ccpj-hx3c\n- Packaging improvments:\n  * Backfill CVE aliases in recent changelog entries\n\n- Update to version 0.0.20241028T152002 2024-10-28T15:20:02Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3207 GHSA-p5wf-cmr4-xrwr\n  * GO-2024-3208 CVE-2024-47825 GHSA-3wwx-63fv-pfq6\n  * GO-2024-3210 CVE-2024-8901\n  * GO-2024-3211 CVE-2024-50312\n  * GO-2024-3212 GHSA-rjfv-pjvx-mjgv\n  * GO-2024-3213 CVE-2024-49380\n  * GO-2024-3214 CVE-2024-49381\n  * GO-2024-3215 CVE-2024-9264 GHSA-q99m-qcv4-fpm7\n  * GO-2024-3216 CVE-2024-49753 GHSA-6cf5-w9h3-4rqv\n  * GO-2024-3217 CVE-2024-49757 GHSA-3rmw-76m6-4gjc\n  * GO-2024-3219 GHSA-7h65-4p22-39j6\n  * GO-2024-3220 CVE-2023-32197 GHSA-7h8m-pvw3-5gh4\n  * GO-2024-3221 CVE-2024-22036 GHSA-h99m-6755-rgwc\n  * GO-2024-3222 GHSA-x7xj-jvwp-97rv\n  * GO-2024-3223 CVE-2022-45157 GHSA-xj7w-r753-vj8v\n  * GO-2024-3224 CVE-2024-39223 GHSA-8wxx-35qc-vp6r\n\n- Update to version 0.0.20241017T153730 date 2024-10-17T15:37:30Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3189 CVE-2024-38365 GHSA-27vh-h6mc-q6g8\n  * GO-2024-3203 CVE-2024-9486\n  * GO-2024-3204 CVE-2024-9594\n\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3189 CVE-2024-38365 GHSA-27vh-h6mc-q6g8\n  * GO-2024-3196 CVE-2024-47877 GHSA-8rm2-93mq-jqhc\n  * GO-2024-3199 GHSA-vv6c-69r6-chg9\n  * GO-2024-3200 CVE-2024-48909 GHSA-3c32-4hq9-6wgj\n  * GO-2024-3201 CVE-2023-22644\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3166 CVE-2024-47534 GHSA-4f8r-qqr9-fq8j\n  * GO-2024-3171 CVE-2024-9341 GHSA-mc76-5925-c5p6\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-3161 CVE-2024-22030 GHSA-h4h5-9833-v2p4\n  * GO-2024-3162 CVE-2024-7594 GHSA-jg74-mwgw-v6x3\n  * GO-2024-3163 CVE-2024-47182\n  * GO-2024-3164 CVE-2024-47003 GHSA-59hf-mpf8-pqjh\n  * GO-2024-3166 CVE-2024-47534 GHSA-4f8r-qqr9-fq8j\n  * GO-2024-3167 CVE-2024-9355 GHSA-3h3x-2hwv-hr52\n  * GO-2024-3168 CVE-2024-8975 GHSA-chqx-36rm-rf8h\n  * GO-2024-3169 CVE-2024-9407 GHSA-fhqq-8f65-5xfc\n  * GO-2024-3170 CVE-2024-8996 GHSA-m5gv-m5f9-wgv4\n  * GO-2024-3172 CVE-2024-33662 GHSA-9mjw-79r6-c9m8\n  * GO-2024-3173 CVE-2024-7558 GHSA-mh98-763h-m9v4\n  * GO-2024-3174 CVE-2024-8037 GHSA-8v4w-f4r9-7h6x\n  * GO-2024-3175 CVE-2024-8038 GHSA-xwgj-vpm9-q2rq\n  * GO-2024-3179 CVE-2024-47616 GHSA-r7rh-jww5-5fjr\n  * GO-2024-3181 CVE-2024-9313 GHSA-x5q3-c8rm-w787\n  * GO-2024-3182 GHSA-wpr2-j6gr-pjw9\n  * GO-2024-3184 CVE-2024-36814 GHSA-9cp9-8gw2-8v7m\n  * GO-2024-3185 CVE-2024-47832\n  * GO-2024-3186 CVE-2024-9675 GHSA-586p-749j-fhwp\n  * GO-2024-3188 CVE-2024-9312 GHSA-4gfw-wf7c-w6g2\n  * GO-2024-3190 CVE-2024-47067 GHSA-8pph-gfhp-w226\n  * GO-2024-3191 CVE-2024-9180 GHSA-rr8j-7w34-xp5j","status":"published","published":"2024-11-05T14:52:20Z","modified":"2026-02-04T12:23:04.839834Z","updated_at":"2026-11-02T16:58:33.135986Z"},{"id":"openSUSE-SU-2024:14447-1","title":"govulncheck-vulndb-0.0.20241030T212825-1.1 on GA media","description":"These are all security issues fixed in the govulncheck-vulndb-0.0.20241030T212825-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-11-01T00:00:00Z","modified":"2026-02-04T03:23:32.319637Z","updated_at":"2026-11-02T16:58:36.976155Z"},{"id":"SUSE-SU-2024:3911-1","title":"Security update for govulncheck-vulndb","description":"This update for govulncheck-vulndb fixes the following issues:\n\nUpdate to version 0.0.20241030T212825 2024-10-30T21:28:25Z ( jsc#PED-11136 )\n\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3230 CVE-2024-48921 GHSA-qjvc-p88j-j9rm\n  * GO-2024-3232 CVE-2024-10241 GHSA-6mvp-gh77-7vwh\n\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3226 CVE-2024-47827 GHSA-ghjw-32xw-ffwr\n  * GO-2024-3227 CVE-2024-10214 GHSA-hm57-h27x-599c\n  * GO-2024-3228 GHSA-wcx9-ccpj-hx3c\n\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3207 GHSA-p5wf-cmr4-xrwr\n  * GO-2024-3208 CVE-2024-47825 GHSA-3wwx-63fv-pfq6\n  * GO-2024-3210 CVE-2024-8901\n  * GO-2024-3211 CVE-2024-50312\n  * GO-2024-3212 GHSA-rjfv-pjvx-mjgv\n  * GO-2024-3213 CVE-2024-49380\n  * GO-2024-3214 CVE-2024-49381\n  * GO-2024-3215 CVE-2024-9264 GHSA-q99m-qcv4-fpm7\n  * GO-2024-3216 CVE-2024-49753 GHSA-6cf5-w9h3-4rqv\n  * GO-2024-3217 CVE-2024-49757 GHSA-3rmw-76m6-4gjc\n  * GO-2024-3219 GHSA-7h65-4p22-39j6\n  * GO-2024-3220 CVE-2023-32197 GHSA-7h8m-pvw3-5gh4\n  * GO-2024-3221 CVE-2024-22036 GHSA-h99m-6755-rgwc\n  * GO-2024-3222 GHSA-x7xj-jvwp-97rv\n  * GO-2024-3223 CVE-2022-45157 GHSA-xj7w-r753-vj8v\n  * GO-2024-3224 CVE-2024-39223 GHSA-8wxx-35qc-vp6r\n\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3189 CVE-2024-38365 GHSA-27vh-h6mc-q6g8\n  * GO-2024-3203 CVE-2024-9486\n  * GO-2024-3204 CVE-2024-9594\n\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3189 CVE-2024-38365 GHSA-27vh-h6mc-q6g8\n  * GO-2024-3196 CVE-2024-47877 GHSA-8rm2-93mq-jqhc\n  * GO-2024-3199 GHSA-vv6c-69r6-chg9\n  * GO-2024-3200 CVE-2024-48909 GHSA-3c32-4hq9-6wgj\n  * GO-2024-3201 CVE-2023-22644\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3166 CVE-2024-47534 GHSA-4f8r-qqr9-fq8j\n  * GO-2024-3171 CVE-2024-9341 GHSA-mc76-5925-c5p6\n\n- Go CVE Numbering Authority IDs added or updated with aliases:\n\n  * GO-2024-3161 CVE-2024-22030 GHSA-h4h5-9833-v2p4\n  * GO-2024-3162 CVE-2024-7594 GHSA-jg74-mwgw-v6x3\n  * GO-2024-3163 CVE-2024-47182\n  * GO-2024-3164 CVE-2024-47003 GHSA-59hf-mpf8-pqjh\n  * GO-2024-3166 CVE-2024-47534 GHSA-4f8r-qqr9-fq8j\n  * GO-2024-3167 CVE-2024-9355 GHSA-3h3x-2hwv-hr52\n  * GO-2024-3168 CVE-2024-8975 GHSA-chqx-36rm-rf8h\n  * GO-2024-3169 CVE-2024-9407 GHSA-fhqq-8f65-5xfc\n  * GO-2024-3170 CVE-2024-8996 GHSA-m5gv-m5f9-wgv4\n  * GO-2024-3172 CVE-2024-33662 GHSA-9mjw-79r6-c9m8\n  * GO-2024-3173 CVE-2024-7558 GHSA-mh98-763h-m9v4\n  * GO-2024-3174 CVE-2024-8037 GHSA-8v4w-f4r9-7h6x\n  * GO-2024-3175 CVE-2024-8038 GHSA-xwgj-vpm9-q2rq\n  * GO-2024-3179 CVE-2024-47616 GHSA-r7rh-jww5-5fjr\n  * GO-2024-3181 CVE-2024-9313 GHSA-x5q3-c8rm-w787\n  * GO-2024-3182 GHSA-wpr2-j6gr-pjw9\n  * GO-2024-3184 CVE-2024-36814 GHSA-9cp9-8gw2-8v7m\n  * GO-2024-3185 CVE-2024-47832\n  * GO-2024-3186 CVE-2024-9675 GHSA-586p-749j-fhwp\n  * GO-2024-3188 CVE-2024-9312 GHSA-4gfw-wf7c-w6g2\n  * GO-2024-3190 CVE-2024-47067 GHSA-8pph-gfhp-w226\n  * GO-2024-3191 CVE-2024-9180 GHSA-rr8j-7w34-xp5j","status":"published","published":"2024-11-05T07:45:02Z","modified":"2026-02-05T08:02:05.10845Z","updated_at":"2026-11-02T15:53:55.639015Z"},{"id":"SUSE-SU-2025:0429-1","title":"Security update for govulncheck-vulndb","description":"This update for govulncheck-vulndb fixes the following issues:\n\n- Update to version 0.0.20250207T224745 2025-02-07T22:47:45Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2025-3456 CVE-2025-24786 GHSA-9r4c-jwx3-3j76\n  * GO-2025-3457 CVE-2025-24787 GHSA-c7w4-9wv8-7x7c\n  * GO-2025-3458 CVE-2025-24366 GHSA-vj7w-3m8c-6vpx\n\n- Update to version 0.0.20250206T175003 2025-02-06T17:50:03Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2023-1867 CVE-2022-47930 GHSA-c58h-qv6g-fw74\n  * GO-2024-3244 CVE-2024-50354 GHSA-cph5-3pgr-c82g\n\n- Update to version 0.0.20250206T165438 2025-02-06T16:54:38Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2025-3428 CVE-2025-22867\n  * GO-2025-3447 CVE-2025-22866\n\n- Update to version 0.0.20250205T232745 2025-02-05T23:27:45Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2025-3408\n  * GO-2025-3448 GHSA-23qp-3c2m-xx6w\n  * GO-2025-3449 GHSA-mx2j-7cmv-353c\n  * GO-2025-3450 GHSA-w7wm-2425-7p2h\n  * GO-2025-3454 GHSA-mj4v-hp69-27x5\n  * GO-2025-3455 GHSA-vqv5-385r-2hf8\n\n- Update to version 0.0.20250205T003520 2025-02-05T00:35:20Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2025-3451\n\n- Update to version 0.0.20250204T220613 2025-02-04T22:06:13Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2025-3431 CVE-2025-24884 GHSA-hcr5-wv4p-h2g2\n  * GO-2025-3433 CVE-2025-23216 GHSA-47g2-qmh2-749v\n  * GO-2025-3434 CVE-2025-24376 GHSA-fc89-jghx-8pvg\n  * GO-2025-3435 CVE-2025-24784 GHSA-756x-m4mj-q96c\n  * GO-2025-3436 CVE-2025-24883 GHSA-q26p-9cq4-7fc2\n  * GO-2025-3437 GHSA-274v-mgcv-cm8j\n  * GO-2025-3438 CVE-2024-11741 GHSA-wxcc-2f3q-4h58\n  * GO-2025-3442 CVE-2025-24371 GHSA-22qq-3xwm-r5x4\n  * GO-2025-3443 GHSA-r3r4-g7hq-pq4f\n  * GO-2025-3444 CVE-2024-35177\n  * GO-2025-3445 CVE-2024-47770\n\n- Use standard RPM macros to unpack the source and populate a\n  working directory. Fixes build with RPM 4.20.\n\n- Update to version 0.0.20250130T185858 2025-01-30T18:58:58Z.\n  Refs jsc#PED-11136\n  Go CVE Numbering Authority IDs added or updated with aliases:\n  * GO-2024-2842 CVE-2024-3727 GHSA-6wvf-f2vw-3425\n  * GO-2024-3181 CVE-2024-9313 GHSA-x5q3-c8rm-w787\n  * GO-2024-3188 CVE-2024-9312 GHSA-4gfw-wf7c-w6g2\n  * GO-2025-3372 CVE-2024-45339 GHSA-6wxm-mpqj-6jpf\n  * GO-2025-3373 CVE-2024-45341\n  * GO-2025-3383 CVE-2024-45340\n  * GO-2025-3408\n  * GO-2025-3412 CVE-2024-10846 GHSA-36gq-35j3-p9r9\n  * GO-2025-3420 CVE-2024-45336\n  * GO-2025-3421 CVE-2025-22865\n  * GO-2025-3424 CVE-2025-24369\n  * GO-2025-3426 CVE-2025-0750 GHSA-hp5j-2585-qx6g\n  * GO-2025-3427 CVE-2024-13484 GHSA-58fx-7v9q-3g56\n","status":"published","published":"2025-02-11T14:12:30Z","modified":"2026-02-05T00:10:56.097493Z","updated_at":"2026-11-02T15:53:58.883365Z"}]}}