{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-104480","assignerOrgId":"4ac701fe-44e9-4bcd-9585-dd6449257611","state":"PUBLISHED","assignerShortName":"Bugcrowd","dateReserved":"2026-10-02T00:57:11.860Z","datePublished":"2026-10-02T00:57:55.648Z","dateUpdated":"2026-10-02T00:57:55.648Z"},"containers":{"cna":{"providerMetadata":{"orgId":"4ac701fe-44e9-4bcd-9585-dd6449257611","shortName":"Bugcrowd","dateUpdated":"2026-10-02T00:57:55.648Z"},"title":"Improper MLS Welcome roster validation in Discord libdave allows unauthorized group membership","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-390","type":"CWE","description":"CWE-390 Detection of Error Condition Without Action"}]},{"descriptions":[{"lang":"en","cweId":"CWE-863","type":"CWE","description":"CWE-863 Incorrect Authorization"}]}],"affected":[{"vendor":"Discord","product":"libdave","modules":["C++ library"],"collectionURL":"https://github.com","packageName":"discord/libdave","repo":"https://github.com/discord/libdave","programFiles":["cpp/src/mls/session.cpp"],"programRoutines":[{"name":"discord::dave::mls::Session::VerifyWelcomeState"}],"defaultStatus":"unaffected","versions":[{"version":"1.1.0","status":"affected","lessThan":"1.2.0","versionType":"semver"},{"version":"7b15f1fc16f159da0478aa6be909e38f1e957833","status":"affected","lessThan":"9686fbaea864aa19f0675e486672b6a77811b6a1","versionType":"git"}]}],"descriptions":[{"lang":"en","value":"Discord libdave before 1.2.0 did not reject an MLS Welcome message when the resulting group roster contained an unrecognized participant. An attacker in control of the DAVE signaling path (the voice gateway, or an equivalent position able to add, alter, or withhold signaling messages to a client) could cause affected clients to accept an unauthorized member into the end-to-end encrypted media session, compromising the confidentiality and integrity of audio and video."}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N","baseScore":9.4,"baseSeverity":"CRITICAL"}}],"credits":[{"lang":"en","value":"MDL (https://heartbreak.ing)","type":"finder"}],"references":[{"url":"https://github.com/discord/libdave/commit/9686fbaea864aa19f0675e486672b6a77811b6a1","name":"[cpp] restore strict validation of MLS welcome state","tags":["patch"]},{"url":"https://github.com/discord/libdave/releases/tag/v1.2.0/cpp","name":"libdave v1.2.0 release notes","tags":["release-notes"]},{"url":"https://daveprotocol.com/","name":"Discord Audio and Video End-to-End Encryption (DAVE) Protocol Whitepaper","tags":["technical-description"]},{"url":"https://github.com/discord/libdave","tags":["product"]}],"x_generator":{"engine":"cvelib 1.8.0"}}}}