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.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 1
- First seenCVSS 7.8NVD modified 2026-10-14 17:18
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 14
- https://access.redhat.com/errata/RHSA-2026:32990
- https://access.redhat.com/errata/RHSA-2026:39575
- https://access.redhat.com/errata/RHSA-2026:39576
- https://access.redhat.com/errata/RHSA-2026:44232
- https://access.redhat.com/security/cve/CVE-2026-12505
- https://bugzilla.redhat.com/show_bug.cgi?id=2489805
- https://git.samba.org/?p=cifs-utils.git;a=commit;h=972c5b5ff95e3e812bc8daa72d0383654ab0dba7
- https://access.redhat.com/errata/RHSA-2026:32990
- https://access.redhat.com/errata/RHSA-2026:39575
- https://access.redhat.com/errata/RHSA-2026:39576
- https://access.redhat.com/errata/RHSA-2026:44232
- https://access.redhat.com/security/cve/CVE-2026-12505
- https://bugzilla.redhat.com/show_bug.cgi?id=2489805
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12505.json