{"id":"CVE-2026-16141","aliases":["EUVD-2026-78573","GHSA-28w7-pg33-g2hj"],"status":"published","title":"OpenBMC IPMI Authentication Bypass via Default userKey and Stale Challenge Value","description":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","severity":{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00537,"percentile":0.45572,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-457","CWE-798"],"published":"2026-09-15T13:57:28Z","modified":"2026-10-28T02:30:55Z","products":[{"vendor":"openbmc","product":"phosphor-net-ipmid"}],"references":[{"url":"https://www.runzero.com/advisories/openbmc-ipmi-auth-bypass-rakp-cve-2026-16141/","tags":["third-party-advisory","advisory"]},{"url":"https://www.runzero.com/blog/lights-out-exposed/","tags":["related","article"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-16141","tags":["advisory"]},{"url":"https://www.runzero.com/advisories/openbmc-ipmi-auth-bypass-rakp-cve-2026-16141"},{"url":"https://www.runzero.com/blog/lights-out-exposed"},{"url":"https://github.com/advisories/GHSA-28w7-pg33-g2hj"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16141.json","tags":["advisory"]},{"url":"https://github.com/openbmc/phosphor-net-ipmid","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-16141","title":"OpenBMC IPMI Authentication Bypass via Default userKey and Stale Challenge Value","description":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","status":"published","published":"2026-09-15T13:57:28.846Z","modified":"2026-09-15T14:59:11.232Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-798","CWE-457"],"updated_at":"2026-11-02T14:20:11.24076Z"}],"euvd":[{"id":"EUVD-2026-78573","description":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","status":"published","published":"2026-09-15T13:57:28Z","modified":"2026-09-15T14:59:11Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T17:28:18.105573Z"}],"ghsa":[{"id":"GHSA-28w7-pg33-g2hj","title":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an...","description":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","status":"published","published":"2026-09-15T15:32:11Z","modified":"2026-09-15T15:32:19Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-457"],"updated_at":"2026-11-02T15:11:54.134441Z"}],"nvd":[{"id":"CVE-2026-16141","description":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","status":"published","published":"2026-09-15T14:16:50.43Z","modified":"2026-09-18T19:30:42.73Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-457","CWE-798"],"updated_at":"2026-11-02T14:12:47.668237Z"}],"osv":[{"id":"CVE-2026-16141","title":"OpenBMC IPMI Authentication Bypass via Default userKey and Stale Challenge Value","description":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","status":"published","published":"2026-09-15T13:57:28.846Z","modified":"2026-10-28T02:30:55.558877151Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-457","CWE-798"],"updated_at":"2026-11-02T15:44:57.682091Z"}]}}