CVEvulnerability
CVE-2026-46195
9.8 CRITICAL
Official page ↗
- Status
- Modified
- Published
- 2026-05-28
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- CVSS 3.1 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)
- 7.5 HIGH — CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-190, CWE-476, CWE-787
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.
Affected configurations
• linux linux kernel (>= 5.12 < 6.6.140)
• linux linux kernel (>= 6.7 < 6.12.88)
• linux linux kernel (>= 6.13 < 6.18.30)
• linux linux kernel (>= 6.19 < 7.0.7)
• linux linux kernel 7.1
Related
References
- https://git.kernel.org/stable/c/3b1ddba19e77ee35241cd27f16dc3e8d14e08db7 Patch
- https://git.kernel.org/stable/c/5de2665e913a10ad70aaeecf736b97276e83d995 git.kernel.org
- https://git.kernel.org/stable/c/8bd07e417b6bda67e317920584e48cb6ee442a8a Patch
- https://git.kernel.org/stable/c/ba7f71b6161c0943dafc367565e5843d16b7d505 Patch
- https://git.kernel.org/stable/c/c688f3ed73d31943334ad2139cb02ec49664322a Patch
- https://git.kernel.org/stable/c/f98b48151cc502ada59d9778f0112d21f2586ca3 Patch
- https://git.kernel.org/stable/c/f9dc3be8f403c1216df73e57221f44b045e7ee0b git.kernel.org
- https://access.redhat.com/errata/RHSA-2026:21556 access.redhat.com
- https://access.redhat.com/errata/RHSA-2026:21706 access.redhat.com
- https://access.redhat.com/errata/RHSA-2026:21745 access.redhat.com
- https://access.redhat.com/security/cve/CVE-2026-46195 access.redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2482606 bugzilla.redhat.com
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html cert-portal.siemens.com
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46195.json security.access.redhat.com