CVE-2026-14940 389-ds-base: 389-ds-base: heap-buffer-overflow in dn normalization via quoted multivalued rdn
An unauthenticated remote attacker can cause a heap-buffer-overflow and denial of service in 389 Directory Server by sending a crafted LDAP search request.
- 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-2026-14940?
CVE-2026-14940 is a medium-severity memory corruption vulnerability in Redhat Enterprise Linux, published on 7 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A heap-buffer-overflow flaw was found in 389 Directory Server (389-ds-base). When normalizing a Distinguished Name (DN) that contains a legacy-quoted value encoding a multivalued nested Relative Distinguished Name (RDN), the server can write past the end of a heap allocation while sorting RDN attribute-value pairs. An unauthenticated remote attacker can trigger this condition by sending an LDAP operation whose DN reaches the DN normalization routine, such as a search with a crafted base DN. This can corrupt heap memory and may cause denial of service.
Weakness: CWE-122
Which versions are affected by CVE-2026-14940?
It affects 3 products.
Products include Redhat 389 Directory Server, Redhat Directory Server, Redhat Enterprise Linux.
How do I fix CVE-2026-14940?
No fix has been published for CVE-2026-14940 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-14940 being exploited?
There is no known exploitation of CVE-2026-14940 in the wild and no public exploit code.
Other vulnerabilities in Redhat Enterprise Linux
- CVE-2026-11770 389-ds-base: 389-ds-base: pre-auth ldap filter injection in cleanallruv status check
- CVE-2026-15722 Memory corruption in Red Hat Directory Server 11.5 E4S for RHEL 8
- CVE-2026-9064 Denial of service in Red Hat Directory Server 11.5 E4S for RHEL 8
- CVE-2010-2222 Null dereference in Red Hat Directory Server
- CVE-2026-11611 389-ds-base: 389-ds-base: content sync plugin unbounded queue growth and race conditions
Sources
Also known as AZL-92189, DEBIAN-CVE-2026-14940, GHSA-868f-j5w9-5jgm, UBUNTU-CVE-2026-14940.