CVE-2026-127101

Sssd: sssd: null pointer dereference in pam responder when protocol version negotiation is skipped

Published Nov 12, 2026 CVSS 3.1 · 5.5 Medium EPSS n/a KEV · Not listed
Description
A flaw was found in SSSD's PAM responder. A local attacker can send an authentication request without first negotiating the client protocol version. The responder dereferences a NULL protocol-version pointer and crashes, disrupting SSSD-backed authentication. Repeated crafted requests can sustain the denial of service.

Remediation

Vendor Workaround

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Description A flaw was found in SSSD's PAM responder. A local attacker can send an authentication request without first negotiating the client protocol version. The responder dereferences a NULL protocol-version pointer and crashes, disrupting SSSD-backed authentication. Repeated crafted requests can sustain the denial of service.
Title Sssd: sssd: null pointer dereference in pam responder when protocol version negotiation is skipped
First Time appeared Redhat
Redhat enterprise Linux
Redhat openshift
Redhat rhel Els
Weaknesses CWE-476
CPEs cpe:/a:redhat:enterprise_linux:10
cpe:/a:redhat:enterprise_linux:8
cpe:/a:redhat:enterprise_linux:9
cpe:/a:redhat:openshift:4
cpe:/a:redhat:openshift:5
cpe:/o:redhat:rhel_els:6
cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat
Redhat enterprise Linux
Redhat openshift
Redhat rhel Els
References
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 12, 2026, 5:55 PM
Reserved
Nov 12, 2026, 2:41 PM
Status
Awaiting Analysis
Published
Nov 12, 2026, 6:17 PM
Modified
Nov 12, 2026, 6:17 PM
Severity
Moderate
Public date
Nov 12, 2026, 4:37 PM