CVE-2026-12505
HIGH 7.8A 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.
Severe if exploited (CVSS 7.8), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.1%chance of exploitation in 30 days · 2nd percentile
Impact if exploited
7.8CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ⚠Access: Requires local access to the host
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Affected
Vendors Red Hat
Products Red Hat Enterprise Linux 10 Red Hat Enterprise Linux 6 Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 9 Red Hat Openshift Container Platform 4 Red Hat Enterprise Linux Appstream (V. 10) Red Hat Enterprise Linux Baseos (V. 10)
Weakness (CWE)
- CWE-250
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H