CVE-2026-104039 (GCVE-0-2026-104039)

Vulnerability from cvelistv5 – Published: 2026-10-06 01:00 – Updated: 2026-10-16 10:57
VLAI
Title
Sssd: sssd: denial of service via stale connection state reuse in pam gssapi responder
Summary
A flaw was found in SSSD. A local user can cause a denial of service (DoS) by disrupting system authentication services. When handling Generic Security Services Application Programming Interface (GSSAPI) authentication in the Pluggable Authentication Module (PAM) responder, cached connection state is freed upon completion without clearing the reference pointer. An attacker can exploit this by sending an additional request over the same connection, causing the service to access invalid memory and unexpectedly terminate.
Severity
4.7 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-08 02:39 UTC
CWE
  • CWE-825 - Expired Pointer Dereference
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1036 records in the last 180 days details
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-104039 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2478956 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-10-06 00:41
Credits
This issue was discovered by Found by AISLE in partnership with Red Hat.
Show details on NVD website
To clipboard 

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.