CVE-2026-104733 User Impersonation/Authorization Bypass in XMPP Server ejabberd
Attackers can impersonate arbitrary users in ejabberd by exploiting an unvalidated authzid parameter in the SASL-PLAIN mechanism.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-104733?
CVE-2026-104733 is a high-severity authentication bypass vulnerability in ProcessOne ejabberd, published on 2 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
User Impersonation in ProcessOnes XMMP Server ejabberd <= 26.04 allows an attacker to impersonate arbitrary users via unvalidated authzid parameter in SASL-PLAIN mechanism.
Weakness: CWE-290
Which versions are affected by CVE-2026-104733?
How do I fix CVE-2026-104733?
Upgrade to a fixed version.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-104733 being exploited?
There is no known exploitation of CVE-2026-104733 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-104733, GHSA-339c-8fr4-g2w4, UBUNTU-CVE-2026-104733.