Snap7 through 1.4.3 contains an out-of-bounds write vulnerability in the passive partner that allows a malicious active partner to overflow application buffers by declaring an unvalidated BSend total length. Attackers connecting from the configured peer address can declare up to 65535 bytes and send a short fragment, causing BRecv to memcpy past the buffer and crash or corrupt SCADA, HMI or gateway processes.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Fri, 23 Oct 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 23 Oct 2026 12:00:00 +0000

Type Values Removed Values Added
Description Snap7 through 1.4.3 contains an out-of-bounds write vulnerability in the passive partner that allows a malicious active partner to overflow application buffers by declaring an unvalidated BSend total length. Attackers connecting from the configured peer address can declare up to 65535 bytes and send a short fragment, causing BRecv to memcpy past the buffer and crash or corrupt SCADA, HMI or gateway processes.
Title Snap7 through 1.4.3 Out-of-Bounds Write via BRecv and CheckAsBRecvCompletion
First Time appeared Snap7 Project
Snap7 Project snap7
Weaknesses CWE-787
CPEs cpe:2.3:a:snap7_project:snap7:*:*:*:*:*:*:*:*
Vendors & Products Snap7 Project
Snap7 Project snap7
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H'}

cvssV4_0

{'score': 8.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-10-23T14:59:52.690Z

Reserved: 2026-10-23T11:26:42.748Z

Link: CVE-2026-115723

cve-icon Vulnrichment

Updated: 2026-10-23T14:48:44.118Z

cve-icon NVD

Status : Deferred

Published: 2026-10-23T12:18:12.983

Modified: 2026-10-23T15:17:30.323

Link: CVE-2026-115723

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-23T16:15:17Z

Weaknesses