Security readout for executives and security teams
Plain-English summary
Certain Rockwell controllers can be forced into a communication denial-of-service condition by malformed CIP connection requests. The issue affects controller availability, not confidentiality or data integrity, but in industrial environments lost controller communications can interrupt operations. The provided sources rate it medium, with CVSS 3.1 score 5.8.
Executive priority
Treat as a moderate operational availability risk. Prioritize sites where affected controllers support production, safety-adjacent, or high-cost processes, especially if network access to controllers is broad or poorly segmented.
Technical view
The flaw is improper input validation/control-flow handling in the connection establishment algorithm. Specially crafted CIP packet requests can trigger an infinite loop in CompactLogix 5370 and ControlLogix 5570 controllers version 33 and prior, causing denial-of-service conditions in communications with other products.
Likely exposure
Exposure is likely where affected Rockwell controller families are deployed and reachable by systems or users able to send CIP requests. Internet exposure is not stated in the source bundle; validate plant network segmentation and controller reachability.
Exploitation context
The source bundle does not identify active exploitation, and KEV status is false. The issue is remotely reachable over the network per CVSS, requires low attack complexity, no privileges, and no user interaction, but the documented impact is limited to availability.
Researcher notes
Evidence supports CWE-20 improper input validation leading to an infinite loop during CIP connection establishment. Affected entries include several CompactLogix, GuardLogix, Armor GuardLogix, and ControlLogix 5570 product families, but the bundle does not provide detailed fixed versions.
Mitigation direction
- Review Rockwell and CISA advisories for vendor-approved firmware or mitigation guidance.
- Restrict CIP access to trusted engineering and control-network systems only.
- Segment controller networks from enterprise and internet-facing networks.
- Monitor controllers for unexpected communication loss or repeated connection-establishment failures.
Validation and detection
- Inventory affected Rockwell CompactLogix 5370 and ControlLogix 5570 controller families.
- Confirm whether deployed controller firmware is version 33 or prior where applicable.
- Map which hosts can send CIP requests to affected controllers.
- Review operational logs for denial-of-service symptoms affecting controller communications.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
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ATT&CK lookup starting points
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CWE-20: Exact CWE lookup
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Open ATT&CK lookupCVE-2020-6998 mapping review
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Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L3.91.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.8MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://www.cisa.gov/uscert/ics/advisories/icsa-21-061-02CVE reference · x_refsource_CONFIRM
- https://rockwellautomation.custhelp.com/app/answers/answer_view/a_id/1130398CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.