{"id":"CVE-2026-104480","title":"Improper MLS Welcome roster validation in Discord libdave allows unauthorized group membership","summary":"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 abl…","severity":"critical","cvss":9.4,"cvssVector":"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","cvssSource":"cna","cwe":["CWE-390","CWE-863"],"vendor":"Discord","product":"discord/libdave","affected":["discord/libdave >= 1.1.0 < 1.2.0","discord/libdave >= 7b15f1fc16f159da0478aa6be909e38f1e957833 < 9686fbaea864aa19f0675e486672b6a77811b6a1"],"published":"2026-10-02","updated":"2026-10-02","sourceUpdated":"2026-10-02T00:57:55.648Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-104480","references":[{"url":"https://github.com/discord/libdave/commit/9686fbaea864aa19f0675e486672b6a77811b6a1","label":"[cpp] restore strict validation of MLS welcome state"},{"url":"https://github.com/discord/libdave/releases/tag/v1.2.0/cpp","label":"libdave v1.2.0 release notes"},{"url":"https://daveprotocol.com/","label":"Discord Audio and Video End-to-End Encryption (DAVE) Protocol Whitepaper"},{"url":"https://github.com/discord/libdave"}],"tags":["cve.org"],"ingestedAt":"2026-10-02T02:07:09.203Z","slug":"CVE-2026-104480","body":"## Overview\n\nDiscord 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.\n\n## Affected\n\n- `discord/libdave >= 1.1.0 < 1.2.0`\n- `discord/libdave >= 7b15f1fc16f159da0478aa6be909e38f1e957833 < 9686fbaea864aa19f0675e486672b6a77811b6a1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":52,"depthScoreParts":{"impact":51.7,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}