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TI-2021-05552 Aliases CVE-2021-22659GHSA-fv9f-8rj8-45rf

Buffer overflow in Rockwell Automation MicroLogix 1400

Priority MEDIUM 47CWE-120Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

Rockwell Automation MicroLogix 1400 Version 21.6 and below may allow a remote unauthenticated attacker to send a specially crafted Modbus packet allowing the attacker to retrieve or modify random values in the register. If successfully exploited, this may lead to a buffer overflow resulting in a denial-of-service condition. The FAULT LED will flash RED and communications may be lost. Recovery from denial-of-service condition requires the fault to be cleared by the user.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01795 78th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
—Rockwell Automation MicroLogix 1400MicroLogix 1400, All series Version 21.6 and below—No fix listedCNA
  • Rockwell Automation MicroLogix 1400 Vendor— Affected MicroLogix 1400, All series Version 21.6 and below Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:rockwellautomation:micrologix_1400_firmware:*:*:*:*:*:*:*:*up to 21.6VulnerableRockwell
cpe:2.3:h:rockwellautomation:micrologix_1400:-:*:*:*:*:*:*:*not specified by NVDRunning onRockwell
  • cpe:2.3:o:rockwellautomation:micrologix_1400_firmware:*:*:*:*:*:*:*:* Versions up to 21.6 Vulnerable ·Rockwell
  • cpe:2.3:h:rockwellautomation:micrologix_1400:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Rockwell

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-22659
  2. 2026-10-03 Alias added: GHSA-fv9f-8rj8-45rf

References

Advisory 2

  • TI-2015-05450 Stack-based buffer overflow on Allen-Bradley MicroLogix 1100 devices before B FRN 15.000… CVSS 3.1CRITICAL 9.8
  • TI-2018-12755 Missing authentication in Rockwell Automation CVSS 3.1HIGH 8.6
  • TI-2015-05452 Allen-Bradley MicroLogix 1100 devices before B FRN 15.000 and 1400 devices before B FRN… CVSS 3.1HIGH 7.5
  • TI-2022-02923 MicroLogix 1100 & 1400 Product Web Server Application Vulnerable to Denial-Of-Service Condition Attack CVSS 3.1HIGH 7.5
  • TI-2021-12535 When an authenticated password change request takes place, this vulnerability could allow… CVSS 3.1HIGH 7.5
  • TI-2015-05448 SQL injection vulnerability on Allen-Bradley MicroLogix 1100 devices before B FRN 15.000… CVSS 2.0MEDIUM 6.5
See all 10 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences