CVE-2026-115723
CVE-2026-115723 · Snap7 through 1.4.3 Out-of-Bounds Write via BRecv and CheckAsBRecvCompletion
This page contains facts from public vulnerability sources. Check the original advisory before updating.
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.
CVSS 8.3 · High · EPSS 0.4%
- Published
- Updated
Stack: system
Affected products and versions
Original sources
- https://github.com/davenardella/snap7/pull/41
- https://github.com/davenardella/snap7/blob/30f37da3114024a71ba93f7fd855c680b97a406f/src/core/s7_partner.cpp#L1126-L1166
- https://github.com/davenardella/snap7/blob/30f37da3114024a71ba93f7fd855c680b97a406f/src/core/s7_partner.cpp#L850-L867
- https://www.vulncheck.com/advisories/snap7-through-1.4.3-out-of-bounds-write-via-brecv-and-checkasbrecvcompletion
- https://nvd.nist.gov/vuln/detail/CVE-2026-115723