CVE-2026-18663

A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function frees the parsed controls array on the Session Tracking critical-control rejection path without clearing the SLAPI_REQCONTROLS pblock slot. Operation teardown then frees the same pointer again, causing a double-free. An unauthenticated remote attacker can trigger this with a single BIND request carrying a critical Session Tracking control, resulting in heap corruption and potential denial of service.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-18663
https://bugzilla.redhat.com/show_bug.cgi?id=2510631

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 10:17

Updated : 2026-08-14 19:07

NVD link : CVE-2026-18663

Mitre link : CVE-2026-18663

CVE.ORG link : CVE-2026-18663

JSON object : View

Products Affected

No product.

CWE

CWE-415

Double Free

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