CVE-2020-6988

mediumpriority · track · 31EPSS 0.040 · 90 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

4.02% (90th) EPSS

CVSS 5 · medium

Is it mine?

17 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-26

Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all versions, RSLogix 500 Software v12.001 and prior, A remote, unauthenticated attacker can send a request from the RSLogix 500 software to the victim’s MicroLogix controller. The controller will then respond to the client with used password values to authenticate the user on the client-side. This method of authentication may allow an attacker to bypass authentication altogether, disclose sensitive information, or leak credentials.

remediations

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

No vendor fix yet; a mitigation is available.

MitigationMicroLogix 1100 Controllercisa_csaf_ot
Rockwell Automation reports that there are currently no mitigations for MicroLogix 1400 series A controllers or MicroLogix 1100 controllers.
MitigationRSLogix 500 Softwarecisa_csaf_ot
Rockwell Automation reports that there are currently no mitigations for MicroLogix 1400 series A controllers or MicroLogix 1100 controllers.
MitigationSeries Acisa_csaf_ot
Rockwell Automation reports that there are currently no mitigations for MicroLogix 1400 series A controllers or MicroLogix 1100 controllers.
MitigationSeries Bcisa_csaf_ot
Rockwell Automation reports that there are currently no mitigations for MicroLogix 1400 series A controllers or MicroLogix 1100 controllers.

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · CISA US

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondaryexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-287USprimaryCWE-603USCWE-603USCWE-603US

affected products (17)

Products and version ranges known to be affected.

MicroLogix 1100 Controller: all versionsall versionscisa_csaf_otUS
RSLogix 500 Software: v12.001 and priorall versionscisa_csaf_otUS
Series A: all versionsall versionscisa_csaf_otUS
Series B: v21.001 and priorall versionscisa_csaf_otUS
Rockwell Automation MicroLogix 1100 Controllerall versionscisa_csaf_otUS
Rockwell Automation RSLogix 500 Software≤ 12.001cisa_csaf_otUS
Rockwell Automation Series Aall versionscisa_csaf_otUS
Rockwell Automation Series B≤ 21.001cisa_csaf_otUS
n/a Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all versions, RSLogix 500 Software v12.001 and prior≤ Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all versions, RSLogix 500 Software v12.001 and priorenisa_euvdEU
Rockwell Automation Inc. Allen Bradley MicroLogix 1100all versionsfstec_bduRU
Rockwell Automation Inc. Allen Bradley MicroLogix 1400 Series Aall versionsfstec_bduRU
Rockwell Automation Inc. Allen Bradley MicroLogix 1400 Series B≤ 21.002fstec_bduRU
Rockwell Automation Inc. RSLogix 500≤ 12.001fstec_bduRU
rockwellautomation micrologix 1100 firmwareall versionsnvdUScpe:2.3:o:rockwellautomation:micrologix_1100_firmware:*:*:*:*:*:*:*:*
rockwellautomation micrologix 1400 a firmwareall versionsnvdUScpe:2.3:o:rockwellautomation:micrologix_1400_a_firmware:*:*:*:*:*:*:*:*
rockwellautomation micrologix 1400 b firmware≤ 21.001nvdUScpe:2.3:o:rockwellautomation:micrologix_1400_b_firmware:*:*:*:*:*:*:*:*
rockwellautomation rslogix 500≤ 12.001nvdUScpe:2.3:a:rockwellautomation:rslogix_500:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-20-070-06Rockwell Automation MicroLogix Controllers and RSLogix 500 Software2020-03-10icsa · cisa_csaf_otUS
Successful exploitation of these vulnerabilities could allow an attacker to gain access to sensitive project file information including passwords.

also known as (5)

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 2020-03-16modified 2026-06-17

related (7,683)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-105133US	high7.3OT critical	79.2% (100th)	KEV	2026-10-04
A vulnerability was detected in Ahsay AhsayCBS up to 10.3.2. This affects the function checkSysPwd of the file com/ahsay/obs/api/ApiStructsAction.java of the component API. Perform…
CVE-2026-82329US	—OT critical	14.4% (97th)	KEV	2026-08-28
JFrog Artifactory contains an authentication weakness that, under default configuration, may allow an unauthenticated attacker with network access to obtain administrative privileg…
CVE-2026-42018US	—OT critical	9.80% (96th)	KEV	2026-08-12
JFrog Artifactory could return an internal anonymous-user token to an unauthenticated caller when anonymous access is disabled, potentially exposing sensitive resources.
CVE-2026-65400US	—OT critical	1.72% (77th)	KEV	2026-08-06
An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, ma…
CVE-2026-16232US	critical9.8OT critical	3.52% (89th)	KEV	2026-07-22
An authentication bypass vulnerability in the Check Point SmartConsole login process allows an unauthenticated remote attacker to obtain an application login token and use it to au…

+7678 more

references (6)

External citations — patches, advisories, analysis.

http://www.nsfocus.net/vulndb/46118 cnnvd
https://nvd.nist.gov/vuln/detail/CVE-2020-6988 cnnvd
https://www.rockwellautomation.com/Patchcnnvd
https://www.us-cert.gov/ics/advisories/icsa-20-070-06 cnnvd
https://www.us-cert.gov/ics/advisories/icsa-20-070-06 enisa_euvd
https://www.us-cert.gov/ics/advisories/icsa-20-070-06Third Party AdvisoryUS Government Resourcenvd

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan