CVE-2026-115505

libsmb2 before 6.3 contains integer overflow vulnerabilities in the DCE/RPC NDR decoder in lib/dcerpc.c that allow heap out-of-bounds reads and writes. A malicious SMB server or machine-in-the-middle on unsigned connections can send crafted NetrShareEnum replies with wrapping actual_count or max_count values when clients call smb2_share_enum_async(), corrupting heap memory.

CVSS v3 7.6 HIGH

7.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sahlberg/libsmb2
https://github.com/sahlberg/libsmb2/commit/a79f6914cb5ed3f74293d15cdea901261ce179ff
https://github.com/sahlberg/libsmb2/issues/496
https://github.com/sahlberg/libsmb2/releases/tag/libsmb2-6.3
https://hackmd.io/@haindpwn/libsmb2-dcerpc-ndr-count-overflow-oob
https://www.vulncheck.com/advisories/libsmb2-before-6.3-integer-overflow-in-dce-rpc-ndr-decoder-via-netrshareenum

Configurations

No configuration.

History

22 Oct 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 20:17

Updated : 2026-10-29 13:17

NVD link : CVE-2026-115505

Mitre link : CVE-2026-115505

CVE.ORG link : CVE-2026-115505

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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