CVE-2021-22743 Denial of service in Triconex TCM 4351B installed on Tricon V11.3.x systems.

Low 3.9 Published 26 May 2021 Updated 3 Aug 2024

Malformed packets can reset the Triconex TCM module when the write-protect keyswitch is in the program position, causing a denial of service.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Local or same network only
Victim action needed: Not needed
Fix: None listed

What is CVE-2021-22743?

CVE-2021-22743 is a low-severity denial of service vulnerability in Triconex TCM 4351B installed on Tricon V11.3.x systems., published on 26 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Improper Check for Unusual or Exceptional Conditions vulnerability exists in Triconex TCM 4351B installed on Tricon V11.3.x systems that could cause module reset when TCM receives malformed TriStation packets while the write-protect keyswitch is in the program position.

Weakness: CWE-754

Which versions are affected by CVE-2021-22743?

It affects 2 products.

Products include Schneider-Electric Tcm 4351b Firmware, Schneider-Electric Triconex Model 3009 Mp Firmware.

How do I fix CVE-2021-22743?

No fix has been published for CVE-2021-22743 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-22743 being exploited?

There is no known exploitation of CVE-2021-22743 in the wild and no public exploit code.

Sources

Also known as GHSA-48h6-xg8f-qv46.