CVE-2026-111280

snap7 through 1.4.3 contains an out-of-bounds write vulnerability in TSnap7MicroClient::opReadArea() that allows malicious S7 peers to overflow client buffers via an unchecked DataLength field. Rogue or impersonated PLCs can return crafted ReadVar responses causing memcpy of up to 65535 bytes into caller buffers, crashing SCADA, HMI, or gateway processes and corrupting memory.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/davenardella/snap7
https://github.com/davenardella/snap7/blob/30f37da3114024a71ba93f7fd855c680b97a406f/src/core/s7_micro_client.cpp#L136-L150
https://github.com/davenardella/snap7/issues/31
https://www.vulncheck.com/advisories/snap7-through-1.4.3-out-of-bounds-write-via-tsnap7microclient-opreadarea
https://github.com/davenardella/snap7/issues/31

Configurations

No configuration.

History

23 Oct 2026, 20:17

Type	Values Removed	Values Added
References	~~() https://github.com/davenardella/snap7/issues/31 -~~	() https://github.com/davenardella/snap7/issues/31 -

15 Oct 2026, 22:19

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 22:19

Updated : 2026-10-23 20:17

NVD link : CVE-2026-111280

Mitre link : CVE-2026-111280

CVE.ORG link : CVE-2026-111280

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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