CVE-2026-12505

Summary

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 Software

VendorProductVersion RangeStatus
Red HatRed Hat Enterprise Linux 100:7.6-1.el10_2 < *unaffected

Weaknesses

  • CWE-250: Execution with Unnecessary Privileges

Workarounds

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.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

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

Additional References

References