Threat Intelligence / CVE / CVE-2026-51218

CVE-2026-51218

CVSS v3.1 6.5 (MEDIUM) · Priority 3.3/10 · Published 2026-06-29

As of 2026-06-30, CVE-2026-51218 is a MEDIUM-severity vulnerability, CVSS v3.1 6.5. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-51218, most recently “AI-Powered Attacks Targeting Siemens S7 Series PLCs in U.S. Critical Infrastructure”.

Last updated: 2026-06-30

What is CVE-2026-51218?

A heap buffer overflow in the TS7Worker::PerformFunctionWrite() function (/core/s7_server.cpp) of snap7 v1.4.3 allows attackers to cause a Denial of Service (DoS) via a crafted packet.

The record classifies CVE-2026-51218 under weakness class CWE-122. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on availability. The identifier was first published 76 days ago.

Severity and exploitation probability

CVSS v3.1 base score
6.5 — MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CISA KEV
Not listed in the CISA Known Exploited Vulnerabilities catalog
Threadlinqs priority
3.3/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
Published
2026-06-29, last modified 2026-06-30

Is CVE-2026-51218 being exploited?

It currently carries a trending score of 30 in the Threadlinqs vulnerability feed.

Affected products and versions

No affected-product or package list has been recorded for CVE-2026-51218 in the tracked sources. The vendor advisory and the references below are the authoritative statement of what is affected.

How to fix CVE-2026-51218

No vendor patch reference has been recorded for CVE-2026-51218 in the tracked sources. Follow the references below for a fix, and treat any affected deployment as exposed until the vendor states otherwise.

Threat activity tracking CVE-2026-51218

1 tracked threat in the Threadlinqs corpus references CVE-2026-51218, either in the campaign’s CVE list or as an indicator on the campaign record.

Sources

Enriched from CVE.org. Last verified by Threadlinqs on .

Other references

Full detection coverage & IOCs for threats exploiting CVE-2026-51218 are available via the Threadlinqs MCP server (Purple tier). View plans →

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