CVE-2026-31704

MEDIUM EPSS 1.9%
Published May 1, 20261mo ago · Modified Jun 17, 20261w ago
5.5 CVSS 3.1
Medium
Find Similar
Published May 1, 2026 1mo ago
Last Modified Jun 17, 2026 1w ago

Description

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

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
1.9% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 4

VendorProductVersionRange
linuxlinux_kernel*≥5.15  –  <6.6.136
linuxlinux_kernel*≥6.7  –  <6.12.84
linuxlinux_kernel*≥6.13  –  <6.18.25
linuxlinux_kernel*≥6.19  –  <7.0.2

References 6

  • git.kernel.org https://git.kernel.org/stable/c/299f962c0b02d048fb45d248b4da493d03f3175d
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/41e53a773db6342ac9a689ee5ba635c31744c9f0
  • git.kernel.org https://git.kernel.org/stable/c/5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8d5729350b236896f51379588d9a690b7fafb8db
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e1955a94b6f17f4b058afa955a6f187eb3ed7615
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/299f962c0b02d048fb45d248b4da493d03f3175d
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5e7b8f3c539d69b2ed5f2408e2f75e68ce7eef43
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8d5729350b236896f51379588d9a690b7fafb8db
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/e1955a94b6f17f4b058afa955a6f187eb3ed7615
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/ef7902be3f215b6bf7babe4dc9dd9a7d57dad7a7
    Patch