Vulnerability in Red Hat Directory Server 11
CVE-2026-86345
A flaw was found in 389-ds-base. The server does not discard plaintext bytes already buffered from a client connection when negotiating StartTLS, allowing an on-path attacker to inject a crafted LDAP message that is processed after the TLS upgrade and whose response is delivered to the client in place of the client's own pending operation's response, due to messageID collision. This can cause a client application to treat a failed authentication (bind) attempt as successful.
Published .
CVSS v3 metric
CVSS v3 base score 9.0 (Critical). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-86345 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
Frequently asked questions
- What is CVE-2026-86345?
- CVE-2026-86345 is a critical-severity vulnerability in Red Hat Directory Server 11, classified under CWE-923. CVSS score: 9.0/10. Published 2026-10-02.
- How severe is CVE-2026-86345?
- Critical severity. CVSS v3 base score is 9.0 out of 10.