CVE-2026-11790
published 2026-06-09CVE-2026-11790: 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…
PriorityP426medium4.9CVSS 3.1
AVNACLPRHUINSUCNINAH
EPSS
0.29%
21.1th percentile
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
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| port389 | 389-ds-base | — | — |
| redhat-ds_11 | 389-ds-base | — | — |
| redhat-ds_12 | 389-ds-base | — | — |
| redhat | 389_directory_server | — | — |
| redhat | directory_server | — | — |
| redhat | directory_server | — | — |
| redhat | directory_server | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
CVSS provenance
nvdv3.14.9MEDIUMCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
vendor_redhat4.9MEDIUM
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GHSA
A flaw was found in 389 Directory Server.
ghsa_unreviewed·2026-06-09
CVE-2026-11790 [MEDIUM] CWE-400 A flaw was found in 389 Directory Server.
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.
Red Hat
389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service
vendor_redhat·2026-04-16·CVSS 4.9
CVE-2026-11790 [MEDIUM] CWE-400 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service
389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service
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.
Mitigation: 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 unusual
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-11790 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service [fedora-all]
bugzilla·2026-06-30·CVSS 5.7
CVE-2026-11790 [MEDIUM] CVE-2026-11790 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service [fedora-all]
CVE-2026-11790 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
The PBKDF2-SHA256 password storage plugin in 389 Directory Server extracts the iteration count from stored password hashes without an upper bound check. An attacker with Directory Manager privileges can plant a crafted {PBKDF2_SHA256} hash with extreme iteration counts (e.g. 0x7FFFFFFF). Any subsequent LDAP BIND as the poisoned account triggers unbounded CPU consumption, hanging a worker thread for hours and enabling persistent denial of ser
Bugzilla
CVE-2026-11790 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service
bugzilla·2026-06-05·CVSS 5.7
CVE-2026-11790 [MEDIUM] CVE-2026-11790 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service
CVE-2026-11790 389-ds-base: 389-ds-base: PBKDF2 password storage plugin unbounded iteration count denial of service
The PBKDF2-SHA256 password storage plugin in 389 Directory Server extracts the iteration count from stored password hashes without an upper bound check. An attacker with Directory Manager privileges can plant a crafted {PBKDF2_SHA256} hash with extreme iteration counts (e.g. 0x7FFFFFFF). Any subsequent LDAP BIND as the poisoned account triggers unbounded CPU consumption, hanging a worker thread for hours and enabling persistent denial of service.
Both the C plugin (pbkdf2_pwd.c) and Rust plugin (pwdchan/lib.rs) are affected. Distinct from CVE-2024-5953 which added hash length check but not iteration cap.
Introduced in 389-ds-base 1.3.6 (commit 542287ce7, Ticket 397). PoC c
2026-06-09
Published