CVE-2019-6553

highpriority · attend · 62EPSS 0.663 · 99 %ileEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

66.3% (99th) EPSS

CVSS 7.5 · high

Is it mine?

5 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-27

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.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedRSLinx Classiccisa_csaf_ot
NOTE: In RSLinx Classic 4.10 or later, “Accept UDP Messages on Ethernet Port” checkbox is unchecked by default.
MitigationRSLinx Classiccisa_csaf_ot
For more information please see the Rockwell Automation security advisory
https://rockwellautomation.custhelp.com/app/answers/detail/a_id/1085038

cvss

Technical severity, 0–10. One row per scoring source.

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–10

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.010criticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · CISA US

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-119USCWE-121USCWE-121USCWE-121USCWE-787US

affected products (5)

Products and version ranges known to be affected.

RSLinx Classic: Versions 4.10.00 and priorall versionscisa_csaf_otUS
Rockwell Automation RSLinx Classic≤ 4.10.00cisa_csaf_otUS
Rockwell Automation RSLinx Classic≤ 4.10.00 and priorenisa_euvdEU
Rockwell Automation Inc. RSLinx Classic≤ 4.10.00fstec_bduRU
rockwellautomation rslinx≤ 4.10.00nvdUScpe:2.3:a:rockwellautomation:rslinx:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-19-064-01Rockwell Automation RSLinx Classic2019-03-05icsa · cisa_csaf_otUS
Successful exploitation of this vulnerability could allow a remote attacker to execute arbitrary code on the target device.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisa_csaf_ot nvd NVD CVE.org MITRE

published 2019-04-04modified 2026-06-17

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+16123 more

references (10)

External citations — patches, advisories, analysis.

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