CVE-2026-11793 389-ds-base: 389-ds-base: stack buffer overflow in checkprefix() algorithm id parsing

What is CVE-2026-11793?

CVE-2026-11793 is a medium-severity memory corruption vulnerability in Red Hat Directory Server 11, published on 9 Jun 2026. An attacker needs administrator access to exploit it, with no action from the victim.

Official description

A stack buffer overflow flaw was found in 389 Directory Server. The checkPrefix() function in pw.c copies an attacker-controlled algorithm ID into a 256-byte stack buffer without bounds checking when parsing reversible-encrypted attribute values. An attacker with Directory Manager privileges can crash the LDAP server by storing a crafted credential with an oversized algorithm ID. FORTIFY_SOURCE mitigates this to denial of service only.

Weakness: CWE-121

Which versions are affected by CVE-2026-11793?

It affects 1 product.

Products include Redhat 389 Directory Server.

How do I fix CVE-2026-11793?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-11793 being exploited?

There is no known exploitation of CVE-2026-11793 in the wild and no public exploit code.

Other vulnerabilities in Red Hat Directory Server 11

• CVE-2026-11770 389-ds-base: 389-ds-base: pre-auth ldap filter injection in cleanallruv status check High 7.5
• CVE-2026-15722 Memory corruption in Red Hat Directory Server 11.5 E4S for RHEL 8 High 7.5
• CVE-2026-9064 Denial of service in Red Hat Directory Server 11.5 E4S for RHEL 8 High 7.5
• CVE-2010-2222 Null dereference in Red Hat Directory Server High 7.5
• CVE-2026-11611 389-ds-base: 389-ds-base: content sync plugin unbounded queue growth and race conditions Medium 6.5

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2026-11793, GHSA-v6v5-66j3-444p, UBUNTU-CVE-2026-11793.