CVE-2026-110714

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sahlberg/libsmb2
https://github.com/sahlberg/libsmb2/blob/d67e213a5c4e7e4969fd81f0b95e4ca5831fbba1/lib/smb2-data-security-descriptor.c#L266
https://github.com/sahlberg/libsmb2/commit/523abe20be3207011a936db47f1d3bab79c05450
https://hackmd.io/@haind-pwn/libsmb2-query-info-reply-oob-read
https://www.vulncheck.com/advisories/libsmb2-through-6.2-heap-out-of-bounds-read-via-decode-acl-integer-underflow

Configurations

No configuration.

History

14 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 16:17

Updated : 2026-10-20 02:17

NVD link : CVE-2026-110714

Mitre link : CVE-2026-110714

CVE.ORG link : CVE-2026-110714

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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