VDB-372248 · CVE-2026-11791 · GCVE-0-2026-11791

Red Hat Directory Server/Enterprise Linux 389 Directory Server attr_syntax_swap_ht use after free

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.5	$5k-$25k	1.87

Summaryinfo

A vulnerability, which was classified as critical, was found in Red Hat Directory Server and Enterprise Linux. This affects the function attr_syntax_swap_ht of the component 389 Directory Server. Such manipulation leads to use after free. This vulnerability is listed as CVE-2026-11791. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Red Hat Directory Server and Enterprise Linux (affected version not known). It has been rated as critical. Affected by this issue is the function attr_syntax_swap_ht of the component 389 Directory Server. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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).

The advisory is shared for download at access.redhat.com. This vulnerability is handled as CVE-2026-11791 since 06/09/2026. The exploitation is known to be difficult. The attack may be launched remotely. Additional levels of successful authentication are necessary for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 06/18/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Directory Service Software

Vendor

Red Hat

Name

License

open-source

Website

Vendor: https://www.redhat.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.5
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.1
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.0
CNA Vector (redhat): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/09/2026 CVE reserved
06/18/2026 +9 days Advisory disclosed
06/18/2026 +0 days VulDB entry created
06/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: redhat.com

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2026-11791 (🔒)
GCVE (CVE): GCVE-0-2026-11791
GCVE (VulDB): GCVE-100-372248

Entryinfo

Created: 06/18/2026 19:52
Changes: 06/18/2026 19:52 (63)
Complete: 🔍
Cache ID: 216::103