CVE-2026-9064: Red Hat Directory Server 11.5 E4S for RHEL 8 389-ds-base · Unthrottled Resource Allocation
Affects Red Hat Directory Server 11.5 E4S for RHEL 8 389-ds-baseSource CVE Database V5
Not known to be exploited · CVSS 7.5 High.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.8% chance of exploitation in 30 days – higher than 56% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 20 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| 389-ds-base | Affected
| Fixed in– |
GitHub389-ds-basepkg:github/389-ds-baseOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released official security updates for 389-ds-base that address this vulnerability by enforcing limits on LDAP controls count. Users should apply the updated packages as per Red Hat advisories RHSA-2026:26452 and RHSA-2026:26453. The advisories provide detailed instructions and updated package versions for Red Hat Enterprise Linux 7 Extended Lifecycle Support, 8, and 9. No additional mitigation is required beyond applying these official patches.
Description
A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function in the LDAP server does not enforce an upper bound on the number of controls per LDAP message. A remote, unauthenticated attacker can send a specially crafted LDAP request containing hundreds of thousands of minimal controls within the default maximum BER message size (2 MB), causing excessive CPU consumption and heap allocation on the server. Under concurrent exploitation, this leads to significant latency degradation, worker thread starvation, or out-of-memory termination, resulting in a denial of service.
References
- access.redhat.com/errata/RHSA-2026:26452 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26453 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26454 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26455 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26456 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26457 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26458 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26459 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26460 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26461 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26463 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26464 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26465 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26597 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26599 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26639 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:27125 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-9064 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2480093 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-9064.json (opens in a new tab)