Auth bypass in Red Hat Directory Server 11

CVE-2026-18922

A flaw was found in 389 Directory Server. During SASL PLAIN authentication, a stale identity carried in a Cyrus SASL auxiliary property from a prior failed bind attempt can be installed on a connection following a subsequent, unrelated successful bind, regardless of which SASL mechanism completes that second bind. An attacker can send a SASL PLAIN bind as cn=Directory Manager with an incorrect password, then complete a SASL ANONYMOUS bind on the same connection, causing the server to grant Directory Manager authority without any valid credentials. A variant using a valid low-privileged account's own successful bind instead of an anonymous one is also possible.

Vulnerability class: Broken Authentication

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-18922?
CVE-2026-18922 is a critical-severity vulnerability in Red Hat Directory Server 11, classified under Improper Authentication. CVSS score: 9.8/10. Published 2026-09-07.
How severe is CVE-2026-18922?
Critical severity. CVSS v3 base score is 9.8 out of 10.