This vulnerability arises from an integer underflow in the SMD5 password storage plugin of Red Hat Directory Server 11 (389 Directory Server). When a crafted password hash shorter than 16 bytes is processed, the calculation of the salt length underflows as an unsigned integer, leading to a buffer over-read. This results in a denial of service by crashing the LDAP server during authentication attempts. The CVSS 3.1 base score is 4.9, reflecting a network attack vector with low attack complexity but requiring high privileges and no user interaction. There is no indication of confidentiality or integrity impact, only availability is affected.

The vulnerability causes a denial of service condition by crashing the LDAP server during authentication due to a buffer over-read triggered by an integer underflow in the password plugin. There is no reported impact on confidentiality or integrity. No known exploits in the wild have been reported.

Patch status is not yet confirmed — check the vendor advisory at https://access.redhat.com/security/cve/CVE-2026-11789 for current remediation guidance. No official fix or workaround is stated in the provided data. Until a patch is available, restrict access to the LDAP server to trusted users to reduce risk of exploitation.