PT-2026-44318 · Linux · Linux

Published 2026-05-28 · Updated 2026-05-28 · CVE-2026-46195

Mitre

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.

Related Identifiers

CVE-2026-46195

Affected Products

Linux

References · 6

• https://nvd.nist.gov/vuln/detail/CVE-2026-46195 · Security Note
• https://git.kernel.org/stable/c/ba7f71b6161c0943dafc367565e5843d16b7d505 · Note
• https://git.kernel.org/stable/c/c688f3ed73d31943334ad2139cb02ec49664322a · Note
• https://git.kernel.org/stable/c/8bd07e417b6bda67e317920584e48cb6ee442a8a · Note
• https://git.kernel.org/stable/c/3b1ddba19e77ee35241cd27f16dc3e8d14e08db7 · Note
• https://git.kernel.org/stable/c/f98b48151cc502ada59d9778f0112d21f2586ca3 · Note