Vulnerability in Red Hat Enterprise Linux 10
CVE-2026-12505
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (4.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 4.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Red Hat Enterprise Linux 10 — versions 0:7.6-1.el10_2
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8 — versions 0:7.0-5.el8_10
- Red Hat Enterprise Linux 9 — versions 0:7.6-2.el9_8
- Red Hat Openshift Container Platform 4
- Red Hat Openshift Container Platform 4.22 — versions 4.22.9.8.202607220526-0
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2026-12505 (vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking)
- git.samba.org/
- access.redhat.com/errata/RHSA-2026:32990 (vendor-advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- access.redhat.com/errata/RHSA-2026:39576 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:39575 (vendor-advisory)
- access.redhat.com/errata/RHSA-2026:44232 (vendor-advisory)
Frequently asked questions
- What is CVE-2026-12505?
- CVE-2026-12505 is a high-severity vulnerability in Red Hat Enterprise Linux 10, classified under CWE-250. CVSS score: 7.8/10. Published 2026-06-18.
- How severe is CVE-2026-12505?
- High severity. CVSS v3 base score is 7.8 out of 10.