CVE-2026-11790

Summary

A flaw was found in 389 Directory Server. The PBKDF2-SHA256 password storage plugin does not enforce an upper bound on the iteration count extracted from stored password hashes. A privileged attacker who can modify a user's password hash can cause excessive CPU consumption during authentication, resulting in denial of service.

Affected Software

VendorProductVersion RangeStatus

Weaknesses

  • CWE-400: Uncontrolled Resource Consumption

Workarounds

Disable nsslapd-allow-hashed-passwords (default: off) to prevent non-DM users from setting pre-hashed passwords. Restrict Directory Manager credentials; limit DM access to management networks and audit DM operations via nsslapd-auditlog. Monitor for suspicious userPassword modifications (unusual hash schemes or large base64 payloads). Monitor for unusually long bind operations to the same account, which may indicate a poisoned PBKDF2 hash.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References