Vulnerability Description
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.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 5.12, < 6.6.140 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/3b1ddba19e77ee35241cd27f16dc3e8d14e08db7Patch
- https://git.kernel.org/stable/c/5de2665e913a10ad70aaeecf736b97276e83d995
- https://git.kernel.org/stable/c/8bd07e417b6bda67e317920584e48cb6ee442a8aPatch
- https://git.kernel.org/stable/c/ba7f71b6161c0943dafc367565e5843d16b7d505Patch
- https://git.kernel.org/stable/c/c688f3ed73d31943334ad2139cb02ec49664322aPatch
- https://git.kernel.org/stable/c/f98b48151cc502ada59d9778f0112d21f2586ca3Patch
- https://git.kernel.org/stable/c/f9dc3be8f403c1216df73e57221f44b045e7ee0b
- https://access.redhat.com/errata/RHSA-2026:21556
- https://access.redhat.com/errata/RHSA-2026:21706
- https://access.redhat.com/errata/RHSA-2026:21745
- https://access.redhat.com/security/cve/CVE-2026-46195
- https://bugzilla.redhat.com/show_bug.cgi?id=2482606
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46195.json
FAQ
What is CVE-2026-46195?
CVE-2026-46195 is a vulnerability with a CVSS score of 9.8 (CRITICAL). 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_t...
How severe is CVE-2026-46195?
CVE-2026-46195 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-46195?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.