{"id":"CVE-2021-29432","aliases":["GHSA-mh74-4m5g-fcjx","PYSEC-2021-23"],"title":"Malicious users could abuse Sydent to control the content of invitation emails","summary":"Malicious users could abuse Sydent to control the content of invitation emails","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N","vendor":"matrix-sydent","product":"matrix-sydent","ecosystem":"pip","affected":["matrix-sydent < 2.3.0"],"patched":["matrix-sydent 2.3.0"],"published":"2021-04-19","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:49:03.750948873Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-mh74-4m5g-fcjx","references":[{"url":"https://github.com/matrix-org/sydent/security/advisories/GHSA-mh74-4m5g-fcjx"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-29432"},{"url":"https://github.com/matrix-org/sydent/commit/4469d1d42b2b1612b70638224c07e19623039c42"},{"url":"https://github.com/matrix-org/sydent/releases/tag/v2.3.0"},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/matrix-sydent/PYSEC-2021-23.yaml"},{"url":"https://pypi.org/project/matrix-sydent"}],"tags":["osv","pip"],"epss":0.00934,"epssPercentile":0.5868,"ingestedAt":"2026-09-12T03:13:01.711Z","slug":"CVE-2021-29432","body":"## Overview\n\n### 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.\n\n## Affected packages\n\n- `matrix-sydent < 2.3.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `matrix-sydent 2.3.0`","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}