{"id":"CVE-2022-39203","url":"https://www.cyber-defence.io/tools/cve/CVE-2022-39203","generatedAt":"2026-10-27T17:40:26.820Z","title":"Attackers can specify a specific string of characters, which would confuse the bridge into combining an attacker-owned channel and an existing channel, allowing them to grant themselves permissions in the channel.","description":"matrix-appservice-irc is an open source Node.js IRC bridge for Matrix. Attackers can specify a specific string of characters, which would confuse the bridge into combining an attacker-owned channel and an existing channel, allowing them to grant themselves permissions in the channel. The vulnerability has been patched in matrix-appservice-irc 0.35.0. As a workaround operators may disable dynamic channel joining via `dynamicChannels.enabled` to prevent users from joining new channels, which prevents any new channels being bridged outside of what is already bridged, and what is specified in the config.","published":"2022-09-13T19:15:13.000Z","lastModified":"2026-06-17T04:57:55.000Z","status":"Modified","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-269"],"affected":["matrix/matrix irc bridge"],"epss":{"score":0.00863,"percentile":0.58336,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.86%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/matrix-org/matrix-appservice-irc/security/advisories/GHSA-xvqg-mv25-rwvw","tags":["Mitigation","Third Party Advisory"],"source":"security-advisories@github.com"},{"url":"https://matrix.org/blog/2022/09/13/security-release-of-matrix-appservice-irc-0-35-0-high-severity/","tags":["Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/matrix-org/matrix-appservice-irc/security/advisories/GHSA-xvqg-mv25-rwvw","tags":["Mitigation","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://matrix.org/blog/2022/09/13/security-release-of-matrix-appservice-irc-0-35-0-high-severity/","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2022-39203","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}