CVE Catalog

CVE-2026-46243

HighCVSS 7.1
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.38%

30th percentile - higher than 30% of all known CVEs

Summary

In the Linux kernel, a vulnerability in the SMB client was fixed that allowed userspace to create cifs.spnego keys with authority-bearing fields (such as pid, uid, creduid, upcall_target) via request_key(2) or add_key(2). Now only kernel-originating descriptions are accepted.

Risk Assessment

A local user could forge SMB authentication keys, potentially leading to unauthorized access to network resources or privilege escalation.

Recommendation

Update the Linux kernel to a version containing the fix (commit in the smb branch).

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.spnego descriptions cifs.spnego key descriptions contain authority-bearing fields such as pid, uid, creduid, and upcall_target that cifs.upcall treats as kernel-originating inputs. However, userspace can also create keys of this type through request_key(2) or add_key(2), allowing those fields to be supplied without CIFS origin. Only accept cifs.spnego descriptions while CIFS is using its private spnego_cred to request the key.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS