Denial of service in Rockwell Automation CompactLogix 5370 and ControlLogix 5570 Controllers

1) Infinite loop

EUVDB-ID: #VU51180

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-6998

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to the connection establishment algorithm does not sufficiently manage its control flow during execution. A remote attacker can send a specially crafted CIP packet and cause denial of service conditions.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Allen-Bradley Armor Compact GuardLogix 5370: - - 33

Armor GuardLogix Safety Controllers: - - 33

Allen-Bradley CompactLogix 5370 L1: - - 33

Allen-Bradley CompactLogix 5370 L2: - - 33

Allen-Bradley CompactLogix 5370 L3: - - 33

Allen-Bradley Compact GuardLogix 5370: - - 33

ControlLogix 5570 controllers: - - 33

CPE2.3

• cpe:2.3:h:rockwell_automation:allen-bradley_armor_compact_guardlogix_5370:*:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_armor_compact_guardlogix_5370:33:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:armor_guardlogix_safety_controllers:*:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:armor_guardlogix_safety_controllers:33:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compactlogix_5370_l1:*:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compactlogix_5370_l1:33:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compactlogix_5370_l2:*:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compactlogix_5370_l2:33:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compactlogix_5370_l3:*:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compactlogix_5370_l3:33:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:allen-bradley_compact_guardlogix_5370:*:*:*:*:*:*:*:*
• cpe:2.3:h:rockwell_automation:controllogix_5570_controllers:*:*:*:*:*:*:*:*

External links

https://ics-cert.us-cert.gov/advisories/icsa-21-061-02

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.