CVE-2026-9064 389-ds-base: 389-ds-base: unbounded ldap controls count in get_ldapmessage_controls_ext() causes cpu and heap amplification (remote dos)
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.
CVSS 3.1 detail
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitable remotely over the network, without an account and without any user action; an attacker can seriously compromise confidentiality, integrity or availability.
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- Interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Red Hat Directory Server 11 | Versions not published | |
| Red Hat Directory Server 12 | Versions not published | |
| Red Hat Directory Server 13 | Versions not published | |
| Red Hat Enterprise Linux 10 | Versions not published | |
| Red Hat Enterprise Linux 6 | Versions not published | |
| Red Hat Enterprise Linux 7 | Versions not published | |
| Red Hat Enterprise Linux 8 8100020260601102239.25 | earliest → < 8100020260601102239.25e700aa | 8100020260601102239.25e700aa |
| Red Hat Enterprise Linux 9 | Versions not published | |
| Red Hat Directory Server 11.9 for RHEL 8 8100020260601104139.37 | earliest → < 8100020260601104139.37ed7c03 | 8100020260601104139.37ed7c03 |