How severe is CVE-2026-51218?

CVE-2026-51218 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-51218 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-51218?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-51218 published?

CVE-2026-51218 was published on 2026-06-29 and last updated on 2026-06-30.

CVE-2026-51218

CVE-2026-51218 is a medium-severity vulnerability with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-122.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-122
Published: 2026-06-29
Last modified: 2026-06-30

Description

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.

Frequently asked questions

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.
How severe is CVE-2026-51218?: CVE-2026-51218 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-51218 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-51218?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-51218 published?: CVE-2026-51218 was published on 2026-06-29 and last updated on 2026-06-30.

References

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