Vulnerability · Published Jun 18, 2026 · Assigned by redhat
CVE-2026-12505Cifs-utils: local privilege escalation via forged cifs.spnego key description in cifs.upcall
High 7.8
In plain English
A high-severity security flaw in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | cifs-utils | 7.0-5.el8_10 | ALSA-2026:39575 |
| AlmaLinux:9 | cifs-utils | 7.6-2.el9_8 | ALSA-2026:39576 |
| AlmaLinux:8 | cifs-utils-devel | 7.0-5.el8_10 | ALSA-2026:39575 |
| AlmaLinux:9 | cifs-utils-devel | 7.6-2.el9_8 | ALSA-2026:39576 |
| AlmaLinux:8 | pam_cifscreds | 7.0-5.el8_10 | ALSA-2026:39575 |
| AlmaLinux:9 | pam_cifscreds | 7.6-2.el9_8 | ALSA-2026:39576 |
| Debian:12 | cifs-utils | no fix listed | DEBIAN-CVE-2026-12505 |
| Debian:13 | cifs-utils | 2:7.4-1+deb13u1 | DEBIAN-CVE-2026-12505 |
| Debian:14 | cifs-utils | 2:7.8-1 | DEBIAN-CVE-2026-12505 |
| Rocky Linux:10 | cifs-utils | 0:7.6-1.el10_2 | RLSA-2026:32990 |
| Rocky Linux:8 | cifs-utils | 0:7.0-5.el8_10 | RLSA-2026:39575 |
| Rocky Linux:9 | cifs-utils | 0:7.6-2.el9_8 | RLSA-2026:39576 |
| Ubuntu:22.04:LTS | cifs-utils | 2:6.14-1ubuntu0.6 | USN-8496-3 |
| Ubuntu:22.04:LTS | cifs-utils | 2:6.14-1ubuntu0.6 | UBUNTU-CVE-2026-12505 |
| Ubuntu:24.04:LTS | cifs-utils | 2:7.0-2ubuntu0.5 | USN-8496-3 |
| Ubuntu:24.04:LTS | cifs-utils | 2:7.0-2ubuntu0.5 | UBUNTU-CVE-2026-12505 |
| Ubuntu:25.10 | cifs-utils | no fix listed | UBUNTU-CVE-2026-12505 |
| Ubuntu:26.04:LTS | cifs-utils | 2:7.4-1ubuntu0.26.04.3 | UBUNTU-CVE-2026-12505 |
| Ubuntu:26.04:LTS | cifs-utils | 2:7.4-1ubuntu0.26.04.3 | USN-8496-3 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4.22 | see references |
| Red Hat | Red Hat Enterprise Linux 6 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 5 | see references |
Weakness: CWE-250 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- RHSA-2026:32990 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:39575 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:39576 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:44232 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-12505 vdb-entry, x_refsource_REDHAT
- RHBZ#2489805 issue-tracking, x_refsource_REDHAT
- https://git.samba.org/?p=cifs-utils.git;a=commit;h=972c5b5ff95e3e812bc8daa72d0383654ab0dba7
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12505.json x_sadp-csaf-vex