CVE-2026-11793
Description
A stack buffer overflow in 389 Directory Server's checkPrefix() function allows an attacker with Directory Manager privileges to cause a denial of service.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
A stack buffer overflow in 389 Directory Server's checkPrefix() function allows an attacker with Directory Manager privileges to cause a denial of service.
Vulnerability
A stack buffer overflow flaw exists in the checkPrefix() function within pw.c in 389 Directory Server. When parsing reversible-encrypted attribute values, the function copies an attacker-controlled algorithm ID into a 256-byte stack buffer without performing bounds checking. This affects versions of 389 Directory Server used in RHEL 7, RHEL 8, and Fedora 42 [2].
Exploitation
An attacker requires Directory Manager privileges on the target 389 Directory Server. They must store a crafted credential or configuration attribute (like nsDS5ReplicaCredentials) containing an oversized algorithm ID within the reversible-encrypted format {SCHEME-}ciphertext. This crafted data can be injected via cn=config or similar local configuration methods [2].
Impact
Successful exploitation allows an attacker to crash the ns-slapd process, resulting in a denial of service (DoS) for the LDAP server. Due to the FORTIFY_SOURCE mitigation, code execution is not possible on production builds, limiting the impact to a crash (SIGABRT) [2].
Mitigation
This vulnerability has been fixed in 389 Directory Server. Specific patched versions are available for RHEL 7, RHEL 8, and Fedora 42 [2]. Users should update to the patched versions to remediate the issue. No workarounds are described in the available references [1, 2].
AI Insight generated on Jun 9, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.
Patches
0No patches discovered yet.
Vulnerability mechanics
No source-code context for this CVE — mechanics is only generated when we can read the actual fix diff. Without that, the four sections (root cause, attack vector, affected code, fix) would be speculation rather than analysis.
References
3News mentions
0No linked articles in our index yet.