CVE-2021-33576: Cleo Lexicom

Critical severity, CVSS 9.8. EPSS: 1.5% chance of exploitation in the next 30 days.

An issue was discovered in Cleo LexiCom 5.5.0.0. Within the AS2 message, the sender can specify a filename. This filename can include path-traversal characters, allowing the file to be written to an arbitrary location on disk.

Affected products

• Cleo Lexicom: version 5.5.0.0 only

Published 2021-06-18. Last modified 2026-06-17.