{"id":"CVE-2021-29432","aliases":["EUVD-2021-0121","GHSA-mh74-4m5g-fcjx","PYSEC-2021-23"],"status":"published","title":"Malicious users could control the content of invitation emails","description":"Sydent is a reference matrix identity server. A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example. This issue has been fixed in 4469d1d.","severity":{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00934,"percentile":0.60997,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20"],"published":"2021-04-15T20:45:15Z","modified":"2026-10-20T10:53:42Z","fixes":[{"ecosystem":"PyPI","package":"matrix-sydent","fixed_in":["2.3.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.0"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.0"}]}],"versions":["2.0.0","2.0.1","2.1.0","2.2.0"]},{"source":"osv","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"GIT","events":[{"introduced":"0"},{"fixed":"4469d1d42b2b1612b70638224c07e19623039c42"}]},{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.0"}]}],"versions":["2.0.0","2.0.1","2.1.0","2.2.0"]}],"products":[{"vendor":"matrix","product":"sydent"},{"vendor":"matrix-org","product":"sydent"}],"references":[{"url":"https://pypi.org/project/matrix-sydent/","tags":["x_refsource_MISC","x_transferred","Product","Third Party Advisory","package"]},{"url":"https://github.com/matrix-org/sydent/releases/tag/v2.3.0","tags":["x_refsource_MISC","x_transferred","Release Notes","Third Party Advisory","advisory","web"]},{"url":"https://github.com/matrix-org/sydent/security/advisories/GHSA-mh74-4m5g-fcjx","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix","web","advisory"]},{"url":"https://github.com/matrix-org/sydent/commit/4469d1d42b2b1612b70638224c07e19623039c42","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-29432","tags":["advisory"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/matrix-sydent/PYSEC-2021-23.yaml","tags":["web"]},{"url":"https://pypi.org/project/matrix-sydent","tags":["web"]},{"url":"https://github.com/advisories/GHSA-mh74-4m5g-fcjx"}],"sources":{"cve":[{"id":"CVE-2021-29432","title":"Malicious users could control the content of invitation emails","description":"Sydent is a reference matrix identity server. A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example. This issue has been fixed in 4469d1d.","status":"published","published":"2021-04-15T20:45:15Z","modified":"2024-08-03T22:02:51.936Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:33:06.658806Z"}],"euvd":[{"id":"EUVD-2021-0121","description":"Sydent is a reference matrix identity server. A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example. This issue has been fixed in 4469d1d.","status":"published","published":"2021-04-15T20:45:15Z","modified":"2024-08-03T22:02:51Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-03T03:24:45.541615Z"}],"ghsa":[{"id":"GHSA-mh74-4m5g-fcjx","title":"Malicious users could abuse Sydent to control the content of invitation emails","description":"### Impact\n\nA malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example.\n\n### Patches\n\nFixed in 4469d1d, 6b405a8, 65a6e91.\n\nNote that these patches include changes to the *default* email templates. If these templates have been locally modified, they must also be updated.\n\n### For more information\n\nIf you have any questions or comments about this advisory, email us at security@matrix.org.","status":"published","published":"2021-04-19T14:54:24Z","modified":"2024-09-24T17:39:03Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:38:05.526697Z"}],"nvd":[{"id":"CVE-2021-29432","description":"Sydent is a reference matrix identity server. A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example. This issue has been fixed in 4469d1d.","status":"published","published":"2021-04-15T21:15:17.63Z","modified":"2026-06-17T03:47:37.827Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":3.5,"vector":"AV:N/AC:M/Au:S/C:N/I:P/A:N","level":"low","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:06:52.03307Z"}],"osv":[{"id":"CVE-2021-29432","description":"Sydent is a reference matrix identity server. A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example. This issue has been fixed in 4469d1d.","status":"published","published":"2021-04-15T21:15:17.63Z","modified":"2026-10-20T10:53:42.611462159Z","cvss":[{"version":"3.1","score":5.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:19.129331Z"},{"id":"GHSA-mh74-4m5g-fcjx","title":"Malicious users could abuse Sydent to control the content of invitation emails","description":"### Impact\n\nA malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example.\n\n### Patches\n\nFixed in 4469d1d, 6b405a8, 65a6e91.\n\nNote that these patches include changes to the *default* email templates. If these templates have been locally modified, they must also be updated.\n\n### For more information\n\nIf you have any questions or comments about this advisory, email us at security@matrix.org.","status":"published","published":"2021-04-19T14:54:24Z","modified":"2026-09-10T03:49:03.750948873Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"medium"},{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:46:51.811331Z"},{"id":"PYSEC-2021-23","description":"Sydent is a reference matrix identity server. A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example. This issue has been fixed in 4469d1d.","status":"published","published":"2021-04-15T21:15:00Z","modified":"2023-11-08T04:05:33.772633Z","updated_at":"2026-11-02T15:52:52.682031Z"}]}}