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CVE-2026-31704

Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
01/05/2026
Last modified:
06/05/2026

Description

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ksmbd: use check_add_overflow() to prevent u16 DACL size overflow<br /> <br /> set_posix_acl_entries_dacl() and set_ntacl_dacl() accumulate ACE sizes<br /> in u16 variables. When a file has many POSIX ACL entries, the<br /> accumulated size can wrap past 65535, causing the pointer arithmetic<br /> (char *)pndace + *size to land within already-written ACEs. Subsequent<br /> writes then overwrite earlier entries, and pndacl-&gt;size gets a<br /> truncated value.<br /> <br /> Use check_add_overflow() at each accumulation point to detect the<br /> wrap before it corrupts the buffer, consistent with existing<br /> check_mul_overflow() usage elsewhere in smbacl.c.

Impact

Vector 3.x
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 5.50 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High

Base Score 3.x
5.50
Severity 3.x
MEDIUM

Vulnerable products and versions

CPE From Up to
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 5.15 (including) 6.6.136 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.7 (including) 6.12.84 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.13 (including) 6.18.25 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.19 (including) 7.0.2 (excluding)

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools