CVE-2026-12505

Cifs-utils: local privilege escalation via forged cifs.spnego key description in cifs.upcall

Published Jun 18, 2026 CVSS 3.1 · 7.8 High EPSS < 1% KEV · Not listed
Description
A flaw was found in the cifs-utils package where the cifs.upcall helper fails to securely drop its root privileges before looking up user information inside a user-controlled environment. A local, low privileged attacker can exploit this by using a crafted request_key payload to trick the root-owned helper into entering a custom environment (namespace) containing a malicious NSS module. This forces the system to load the attacker's controlled NSS Module and configuration, allowing them to execute arbitrary commands as the root user, elevating their privileges and fully compromising the system.

Remediation

Vendor Workaround

Red Hat is not aware of a practical temporary workaround that fully mitigates this issue or meets Red Hat Product Security's standards for usability, deployment, applicability, or stability. Customers are advised to apply the relevant security updates when they become available.

Tracking

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Advisories

Source ID Title
Debian DSA Debian DSA DSA-6567-1 cifs-utils security update
Ubuntu USN Ubuntu USN USN-8496-1 cifs-utils vulnerability
Ubuntu USN Ubuntu USN USN-8496-3 cifs-utils vulnerability
History
Type Values Removed Values Added
First Time appeared Redhat rhel Els
CPEs cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:rhel_els:6
cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat rhel Els
Type Values Removed Values Added
CPEs cpe:/a:redhat:openshift:5
Type Values Removed Values Added
CPEs cpe:/a:redhat:openshift:4
Type Values Removed Values Added
CPEs cpe:/a:redhat:openshift:4
Type Values Removed Values Added
CPEs cpe:/a:redhat:openshift:4
Type Values Removed Values Added
CPEs cpe:/a:redhat:openshift:4 cpe:/a:redhat:openshift:4.22::el9
References
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:8 cpe:/a:redhat:enterprise_linux:8::crb
cpe:/o:redhat:enterprise_linux:8::baseos
References
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:9 cpe:/a:redhat:enterprise_linux:9::appstream
cpe:/a:redhat:enterprise_linux:9::crb
cpe:/o:redhat:enterprise_linux:9::baseos
References
Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:10 cpe:/o:redhat:enterprise_linux:10.2
References
Type Values Removed Values Added
First Time appeared Redhat cifs-utils
Redhat openshift Container Platform
Vendors & Products Redhat cifs-utils
Redhat openshift Container Platform
Type Values Removed Values Added
References
Metrics threat_severity

None

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

threat_severity

Important

Type Values Removed Values Added
Description A flaw was found in the cifs-utils package where the cifs.upcall helper fails to securely drop its root privileges before looking up user information inside a user-controlled environment. A local, low privileged attacker can exploit this by using a crafted request_key payload to trick the root-owned helper into entering a custom environment (namespace) containing a malicious NSS module. This forces the system to load the attacker's controlled NSS Module and configuration, allowing them to execute arbitrary commands as the root user, elevating their privileges and fully compromising the system.
Title Cifs-utils: local privilege escalation via forged cifs.spnego key description in cifs.upcall
First Time appeared Redhat
Redhat enterprise Linux
Redhat openshift
Weaknesses CWE-250
CPEs cpe:/a:redhat:openshift:4
cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux
Redhat openshift
References
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
redhat
Published
Updated
Nov 4, 2026, 10:04 PM
Reserved
Jun 17, 2026, 10:15 AM
Status
Awaiting Analysis
Published
Jun 18, 2026, 4:16 AM
Modified
Nov 4, 2026, 10:17 PM
Severity
Important
Public date
Jun 16, 2026, 12:00 AM