CVE-2026-11788
A flaw was found in 389 Directory Server. The dereference control plugin does not check for allocation failure before using a BER structure, allowing an unauthenticated remote attacker to crash the LDAP server when the system is under memory pressure.
Executive briefing
The source record describes: A flaw was found in 389 Directory Server. The dereference control plugin does not check for allocation failure before using a BER structure, allowing an unauthenticated remote attacker to crash the LDAP server when the system is under memory pressure. The practical risk depends on whether an affected product/version is present, reachable and configured in an exploitable way. Review the affected-product evidence and linked vendor advisories before assigning exposure status.
Evidence confidence: Moderate Evidence-derived, not an exploitability verdict
Severity & attack characteristics
CVSS vector:CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Technical explanation & impact
The technical mechanism is not expanded beyond the source description unless a referenced advisory supplies additional evidence. Read the linked vendor/CERT advisories for root-cause detail.
Potential impact must be interpreted from the published CVSS impact metrics and the affected component. A CVSS impact score is not proof that a particular asset is exploitable.
Weakness classification
CWE-476Affected products and versions
Products below are parsed from NVD vulnerable CPE configuration entries. Version boundaries are shown as published; verify applicability with the vendor.
| Vendor | Product | Version evidence |
|---|---|---|
| redhat | directory_server | CPE version 11.0 · CPE version 12.0 · CPE version 13.0 |
| redhat | 389_directory_server | Version not specified in CPE |
| redhat | enterprise_linux | CPE version 7.0 · CPE version 8.0 · CPE version 9.0 · CPE version 10.0 |
Remediation & validation
- Identify exposure by comparing the affected product and version ranges with your asset inventory, SBOM and externally exposed services.
- Review the linked vendor security advisory or patch notes. Upgrade to a vendor-confirmed fixed release; do not infer a fixed version from the CVE description.
- Until patched, consider restricting network access or disabling the affected feature where operationally safe. These are temporary controls, not a substitute for a vendor fix.
- Validate the remediation with a version check and vulnerability rescan, then retain change evidence.
No fixed version is displayed unless it is explicitly established by a vendor advisory. Follow the vendor's release notes for exact product and branch applicability.
Vendor advisories, patches & exploit references
- https://access.redhat.com/errata/RHSA-2026:55421 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55422 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55423 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55424 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55425 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55426 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55530 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55532 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55756 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55757 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55758 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:55794 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:56047 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:56048 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:56050 VENDOR secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:79217 VENDOR secalert@redhat.com
- https://access.redhat.com/security/cve/CVE-2026-11788 ADVISORY secalert@redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2485423 ADVISORY secalert@redhat.com