CVE-2026-104480 Improper MLS Welcome roster validation in Discord libdave allows unauthorized group membership
An attacker controlling the signaling path can inject unauthorized members into encrypted Discord media sessions, compromising audio and video confidentiality and integrity.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-104480?
CVE-2026-104480 is a critical missing authorization vulnerability in Discord libdave, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-104480?
How do I fix CVE-2026-104480?
No fix has been published for CVE-2026-104480 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-104480 being exploited?
There is no known exploitation of CVE-2026-104480 in the wild and no public exploit code.
Sources
Also known as GHSA-3q99-x36r-rchh.