How severe is CVE-2019-6553?

CVE-2019-6553 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-2019-6553 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 50% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-6553?

CVE-2019-6553 affects Rockwellautomation Rslinx. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-6553?

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-2019-6553 published?

CVE-2019-6553 was published on 2019-04-04 and last updated on 2026-06-17.

CVE-2019-6553

CVE-2019-6553 is a critical-severity vulnerability in Rockwellautomation Rslinx with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 50% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 50% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Rockwellautomation Rslinx
Published: 2019-04-04
Last modified: 2026-06-17

Description

A vulnerability was found in Rockwell Automation RSLinx Classic versions 4.10.00 and prior. An input validation issue in a .dll file of RSLinx Classic where the data in a Forward Open service request is passed to a fixed size buffer, allowing an attacker to exploit a stack-based buffer overflow condition.

Frequently asked questions

What is CVE-2019-6553?: A vulnerability was found in Rockwell Automation RSLinx Classic versions 4.10.00 and prior. An input validation issue in a .dll file of RSLinx Classic where the data in a Forward Open service request is passed to a fixed size buffer, allowing an attacker to exploit a stack-based buffer overflow condition.
How severe is CVE-2019-6553?: CVE-2019-6553 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-2019-6553 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 50% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-6553?: CVE-2019-6553 affects Rockwellautomation Rslinx. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-6553?: 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-2019-6553 published?: CVE-2019-6553 was published on 2019-04-04 and last updated on 2026-06-17.

References

https://ics-cert.us-cert.gov/advisories/ICSA-19-064-01

Affected products (1)

cpe:2.3:a:rockwellautomation:rslinx:*:*:*:*:classic:*:*:*

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