How severe is CVE-2020-27251?

CVE-2020-27251 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-27251 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27251?

CVE-2020-27251 affects Rockwellautomation Factorytalk Linx. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27251?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-27251 published?

CVE-2020-27251 was published on 2020-11-26 and last updated on 2026-06-17.

CVE-2020-27251

CVE-2020-27251 is a critical-severity vulnerability in Rockwellautomation Factorytalk Linx with a CVSS 3.x base score of 9.8. 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: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 5% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-122
Affected product: Rockwellautomation Factorytalk Linx
Published: 2020-11-26
Last modified: 2026-06-17

Description

A heap overflow vulnerability exists within FactoryTalk Linx Version 6.11 and prior. This vulnerability could allow a remote, unauthenticated attacker to send malicious port ranges, which could result in remote code execution.

Frequently asked questions

What is CVE-2020-27251?: A heap overflow vulnerability exists within FactoryTalk Linx Version 6.11 and prior. This vulnerability could allow a remote, unauthenticated attacker to send malicious port ranges, which could result in remote code execution.
How severe is CVE-2020-27251?: CVE-2020-27251 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-27251 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27251?: CVE-2020-27251 affects Rockwellautomation Factorytalk Linx. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27251?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-27251 published?: CVE-2020-27251 was published on 2020-11-26 and last updated on 2026-06-17.

References

https://us-cert.cisa.gov/ics/advisories/icsa-20-329-01

Affected products (1)

cpe:2.3:a:rockwellautomation:factorytalk_linx:*:*:*:*:*:*:*:*

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