---
id: CVE-2026-110714
title: >-
  libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl
  that allows malicious SMB servers to trigger heap out-of-bounds reads via
  crafted security descriptors
summary: >-
  libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl
  that allows malicious SMB servers to trigger heap out-of-bounds reads via
  crafted security descriptors. Attackers controlling a server or intercepting
  unsigned…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'
cwe:
  - CWE-191
published: '2026-10-14'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T16:17:43.473'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-110714'
references:
  - url: 'https://github.com/sahlberg/libsmb2'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/sahlberg/libsmb2/blob/d67e213a5c4e7e4969fd81f0b95e4ca5831fbba1/lib/smb2-data-security-descriptor.c#L266
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/sahlberg/libsmb2/commit/523abe20be3207011a936db47f1d3bab79c05450
    label: disclosure@vulncheck.com
  - url: 'https://hackmd.io/@haind-pwn/libsmb2-query-info-reply-oob-read'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/libsmb2-through-6.2-heap-out-of-bounds-read-via-decode-acl-integer-underflow
    label: disclosure@vulncheck.com
tags:
  - nvd
ingestedAt: '2026-10-14T16:40:32.116Z'
---

## Overview

libsmb2 through 6.2 contains an integer underflow vulnerability in decode_acl that allows malicious SMB servers to trigger heap out-of-bounds reads via crafted security descriptors. Attackers controlling a server or intercepting unsigned sessions can send an AclSize below 8 in a QUERY_INFO reply, bypassing ACE bounds checks and crashing the client.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.