Severity by source
AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:H
Admin-only schema reload trigger sets PR:H; race condition with concurrent traffic sets AC:H; crash is pure availability impact with no confirmed confidentiality or integrity effect.
AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H
Primary rating from Vendor (redhat).
CVSS VectorNVD
Lifecycle Timeline
2DescriptionNVD
A flaw was found in 389 Directory Server. During schema reload, the attr_syntax_swap_ht() function unconditionally frees attribute syntax information nodes, bypassing the refcount-based deferred deletion used elsewhere in the attribute syntax subsystem. If an administrator triggers schema reload while concurrent LDAP query traffic is active, worker threads may access freed memory, resulting in use-after-free or double-free and a denial of service (server crash).
AnalysisAI
Use-after-free in 389 Directory Server's schema reload path crashes the server when administrative schema reloads race against active LDAP query worker threads. The attr_syntax_swap_ht() function bypasses the refcount-based deferred deletion mechanism used throughout the attribute syntax subsystem, directly freeing nodes that concurrent worker threads may still hold references to. Affected products span Red Hat Directory Server 11, 12, and 13 across RHEL 6 through 10; no public exploit or active exploitation (CISA KEV) has been identified at time of analysis, and the CVSS score of 5.0 reflects the high-complexity, high-privilege prerequisites that substantially reduce real-world risk.
Technical ContextAI
389 Directory Server is Red Hat's enterprise LDAP server, based on the upstream 389-ds-base project. The attribute syntax subsystem manages how directory schema attribute types are defined and interpreted; a refcount-based deferred deletion model is used to safely recycle these nodes while worker threads may still hold pointers. During a schema reload, attr_syntax_swap_ht() unconditionally frees attribute syntax information nodes without decrementing or consulting the refcount, violating the invariant that governs safe reclamation. CWE-416 (Use After Free) applies: freed heap memory is subsequently accessed by LDAP query worker threads that were mid-operation, producing undefined behavior ranging from silent corruption to an exploitable crash. CPE strings confirm affected scope: cpe:2.3:a:red_hat:red_hat_directory_server_11, _12, and _13, as well as the 389-ds-base packages shipped with RHEL 6 through 10.
RemediationAI
The primary remediation is to apply the vendor-issued patch from Red Hat once released; monitor https://access.redhat.com/security/cve/CVE-2026-11791 and the Bugzilla tracker at https://bugzilla.redhat.com/show_bug.cgi?id=2485414 for the specific fixed package versions - no exact patched version number is confirmed in available data at time of analysis. Until a patch is available, administrators can reduce risk by restricting schema reload operations to scheduled maintenance windows with zero active LDAP query traffic, effectively eliminating the race condition. This can be enforced by temporarily halting application-layer LDAP connections (e.g., blocking the LDAP/LDAPS port at the firewall or load balancer) before initiating any schema reload, then re-enabling traffic afterward; the trade-off is a brief, planned service interruption. Additionally, tightly restrict who holds Directory Manager or cn=Directory Manager credentials, since PR:H is the gating prerequisite - reducing the pool of users capable of triggering a schema reload limits exposure. Opportunistic exploitation by external attackers is structurally prevented by the authentication requirement.
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View allVendor StatusVendor
SUSE
Severity: Important| Product | Status |
|---|---|
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Affected |
| openSUSE Leap 16.0 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5 | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE CaaS Platform 4.0 | Affected |
| SUSE Enterprise Storage 6 | Affected |
| SUSE Enterprise Storage 7 | Affected |
| SUSE Enterprise Storage 7.1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP1 | Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP2 | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP3 | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Manager Proxy 4.0 | Affected |
| SUSE Manager Proxy 4.1 | Affected |
| SUSE Manager Proxy 4.2 | Affected |
| SUSE Manager Retail Branch Server 4.0 | Affected |
| SUSE Manager Retail Branch Server 4.1 | Affected |
| SUSE Manager Retail Branch Server 4.2 | Affected |
| SUSE Manager Server 4.0 | Affected |
| SUSE Manager Server 4.1 | Affected |
| SUSE Manager Server 4.2 | Affected |
| openSUSE Leap 15.3 | Affected |
| openSUSE Leap 15.4 | Affected |
| openSUSE Leap 15.5 | Affected |
| openSUSE Leap 15.6 | Affected |
| SUSE Manager Proxy 4.3 LTS | Affected |
| SUSE Manager Retail Branch Server 4.3 LTS | Affected |
| SUSE Manager Server 4.3 LTS | Affected |
| suse/389-ds | Affected |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-37902
GHSA-gxp7-cx54-gr2m