{"id":"CVE-2019-11340","aliases":["EUVD-2022-4932","GHSA-q9h8-gpw5-c95c","PYSEC-2026-843"],"status":"published","title":"Matrix Sydent mishandles emails","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","severity":{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-08","score":0.01802,"percentile":0.78664,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-20"],"published":"2019-04-19T13:35:36Z","modified":"2026-10-20T10:52:18Z","fixes":[{"ecosystem":"PyPI","package":"matrix-sydent","fixed_in":["1.0.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.2"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.2"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.2"}]}]}],"products":[{"vendor":"matrix","product":"sydent"}],"references":[{"url":"https://twitter.com/matrixdotorg/status/1118934335963500545","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://matrix.org/blog/2019/04/18/security-update-sydent-1-0-2/","tags":["x_refsource_MISC","x_transferred","Release Notes","Vendor Advisory","advisory"]},{"url":"https://github.com/matrix-org/sydent/commit/4e1cfff53429c49c87d5c457a18ed435520044fc","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/matrix-org/sydent/compare/7c002cd...09278fb","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2019-11340","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-q9h8-gpw5-c95c","tags":["advisory"]},{"url":"https://matrix.org/blog/2019/04/18/security-update-sydent-1-0-2","tags":["web"]},{"url":"https://pypi.org/project/matrix-sydent","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2019-11340","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2019-04-19T13:35:36Z","modified":"2024-08-04T22:48:09.226Z","updated_at":"2026-11-02T14:32:22.432545Z"}],"euvd":[{"id":"EUVD-2022-4932","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2019-04-19T13:35:36Z","modified":"2024-08-04T22:48:09Z","updated_at":"2026-11-03T02:40:49.362838Z"}],"ghsa":[{"id":"GHSA-q9h8-gpw5-c95c","title":"Matrix Sydent mishandles emails","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2022-05-24T16:43:57Z","modified":"2023-09-01T21:41:51Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:37:02.095916Z"}],"nvd":[{"id":"CVE-2019-11340","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2019-04-19T14:29:00.417Z","modified":"2026-06-17T02:12:44.423Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/Au:N/C:N/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:05:11.426883Z"}],"osv":[{"id":"CVE-2019-11340","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2019-04-19T14:29:00.417Z","modified":"2026-10-20T10:52:18.595903786Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T15:44:10.383287Z"},{"id":"GHSA-q9h8-gpw5-c95c","title":"Matrix Sydent mishandles emails","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2022-05-24T16:43:57Z","modified":"2026-07-07T11:56:08.554826852Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T15:46:54.40888Z"},{"id":"PYSEC-2026-843","title":"Matrix Sydent mishandles emails","description":"util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.","status":"published","published":"2026-07-06T08:03:28.015702Z","modified":"2026-07-07T11:46:05.809734259Z","cvss":[{"version":"3.0","score":5.9,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T15:52:58.117212Z"}]}}