{"id":"CVE-2018-12291","aliases":["DEBIAN-CVE-2018-12291","EUVD-2022-5320","GHSA-v8wm-g9f2-xjv4","PYSEC-2026-664","UBUNTU-CVE-2018-12291","USN-6076-1","openSUSE-SU-2024:11041-1"],"status":"published","title":"Matrix Synapse Security Filtering Flaw","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","severity":{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.01792,"percentile":0.78542,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2018-06-13T14:00:00Z","modified":"2026-10-20T10:50:17Z","fixes":[{"ecosystem":"PyPI","package":"matrix-synapse","fixed_in":["0.31.1"],"sources":["ghsa","osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"matrix-synapse","fixed_in":["0.24.0+dfsg-1ubuntu0.1~esm1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.31.1"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.31.1"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.31.1"}]}]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.24.0+dfsg-1ubuntu0.1~esm1"}]}],"versions":["0.19.2+dfsg-6","0.24.0+dfsg-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.24.0+dfsg-1ubuntu0.1~esm1"}]}],"versions":["0.19.2+dfsg-6","0.24.0+dfsg-1"],"bundled":7},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.43.0-1.1"}]}],"bundled":11}],"products":[{"vendor":"matrix","product":"synapse"}],"references":[{"url":"https://github.com/matrix-org/synapse/releases/tag/v0.31.1","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory","web","report"]},{"url":"https://github.com/matrix-org/synapse/pull/3371","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-12291","tags":["advisory"]},{"url":"https://github.com/matrix-org/synapse/commit/0834b49c6a9b6c597a154d4b2dfcf8fff90699ec","tags":["web"]},{"url":"https://github.com/advisories/GHSA-v8wm-g9f2-xjv4","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2018-12291","tags":["advisory"]},{"url":"https://github.com/matrix-org/synapse","tags":["package"]},{"url":"https://pypi.org/project/matrix-synapse","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2018-12291","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-6076-1","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2018-12291","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-10657","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-12423","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-16515","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-5885","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-11842","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-18835","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2018-12291","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2019-5885","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-10108","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-10109","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-1971","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-26257","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2020-26891","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-29471","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-3449","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-39163","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2021-39164","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2018-12291","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2018-06-13T14:00:00Z","modified":"2024-09-17T03:22:37.808Z","updated_at":"2026-11-02T14:35:06.679212Z"}],"euvd":[{"id":"EUVD-2022-5320","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2018-06-13T14:00:00Z","modified":"2024-09-17T03:22:37Z","updated_at":"2026-11-03T00:28:32.482778Z"}],"ghsa":[{"id":"GHSA-v8wm-g9f2-xjv4","title":"Matrix Synapse Security Filtering Flaw","description":"The `on_get_missing_events` function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2022-05-13T01:49:32Z","modified":"2023-10-06T17:13:12Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T14:37:08.278692Z"}],"nvd":[{"id":"CVE-2018-12291","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2018-06-13T14:29:00.273Z","modified":"2026-06-17T01:37:29.5Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"updated_at":"2026-11-02T14:04:29.837913Z"}],"osv":[{"id":"CVE-2018-12291","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2018-06-13T14:29:00.273Z","modified":"2026-10-20T10:50:17.954027865Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:07.934182Z"},{"id":"DEBIAN-CVE-2018-12291","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"withdrawn","published":"2018-06-13T14:29:00.273Z","modified":"2026-08-11T20:49:48.814657079Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:45:30.290351Z"},{"id":"GHSA-v8wm-g9f2-xjv4","title":"Matrix Synapse Security Filtering Flaw","description":"The `on_get_missing_events` function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2022-05-13T01:49:32Z","modified":"2026-07-06T08:11:16.864300527Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:46:56.981655Z"},{"id":"PYSEC-2026-664","title":"Matrix Synapse Security Filtering Flaw","description":"The `on_get_missing_events` function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2026-07-02T14:13:24.881978Z","modified":"2026-07-06T08:00:38.802498302Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:52:57.671918Z"},{"id":"UBUNTU-CVE-2018-12291","description":"The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.","status":"published","published":"2018-06-13T14:29:00Z","modified":"2026-02-04T02:44:40.679567Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:54:16.544091Z"},{"id":"openSUSE-SU-2024:11041-1","title":"matrix-synapse-1.43.0-1.1 on GA media","description":"These are all security issues fixed in the matrix-synapse-1.43.0-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2024-06-15T00:00:00Z","modified":"2026-02-04T03:22:36.180382Z","updated_at":"2026-11-02T16:58:34.894275Z"},{"id":"USN-6076-1","title":"matrix-synapse vulnerabilities","description":"It was discovered that Synapse incorrectly handled certain inputs. If a\nuser or an automated system were tricked into opening a specially crafted\ninput file, a remote attacker could possibly use this issue to cause a\ndenial of service. (CVE-2019-18835, CVE-2018-12291, CVE-2018-10657)\n\nIt was discovered that Synapse incorrectly handled certain inputs. If a\nuser or an automated system were tricked into opening a specially crafted\ninput file, a remote attacker could possibly use this issue to hijack the\nsession. (CVE-2019-11842, CVE-2018-12423)\n\nIt was discovered that Synapse incorrectly handled certain inputs. If a\nuser or an automated system were tricked into opening a specially crafted\ninput file, a remote attacker could possibly use this issue to perform \nspoofing or user impersonation. (CVE-2019-5885, CVE-2018-16515)\n","status":"published","published":"2023-05-16T07:45:08Z","modified":"2026-02-10T04:43:07Z","updated_at":"2026-11-02T16:58:16.738762Z"}]}}