CVE-2026-46195: Linux Kernel

Critical severity, CVSS 9.8. EPSS: 0.7% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: smb: client: validate dacloffset before building DACL pointers parse_sec_desc(), build_sec_desc(), and the chown path in id_mode_to_cifs_acl() all add the server-supplied dacloffset to pntsd before proving a DACL header fits inside the returned security descriptor. On 32-bit builds a malicious server can return dacloffset near U32_MAX, wrap the derived DACL pointer below end_of_acl, and then slip past the later pointer-based bounds checks. build_sec_desc() and id_mode_to_cifs_acl() can then dereference DACL fields from the wrapped pointer in the chmod/chown rewrite paths. Validate dacloffset numerically before building any DACL pointer and reuse the same helper at the three DACL entry points.

Affected products

• Linux Linux Kernel: from 5.12, before 6.6.140 (fixed in 6.6.140); from 6.7, before 6.12.88 (fixed in 6.12.88); from 6.13, before 6.18.30 (fixed in 6.18.30); from 6.19, before 7.0.7 (fixed in 7.0.7); version 7.1 only

Published 2026-05-28. Last modified 2026-07-15.