CVE-2026-43350: In the Linux kernel, the following vulnerability has been resolved: smb: client: require a full NFS mode SID before rea
Summary
A vulnerability in the Linux kernel's SMB (Server Message Block, the protocol for file sharing) client allows a malicious server to trick the system into reading memory beyond the bounds of a data structure called an ACE (access control entry). The bug occurs because the code checks if an ACE matches a special NFS mode SID (security identifier, a unique value representing users or groups) but doesn't verify the ACE has enough data before reading from it.
Solution / Mitigation
Require num_subauth >= 3 before treating the ACE as an NFS mode SID. This check ensures the ACE carries three subauthorities before the code attempts to read the mode bits from sub_auth[2].
Vulnerability Details
EPSS: 0.0%
May 8, 2026
Classification
Original source: https://nvd.nist.gov/vuln/detail/CVE-2026-43350
First tracked: May 8, 2026 at 02:11 PM
Classified by LLM (prompt v3) · confidence: 95%