CVE-2021-47667: Zend Zendto

Critical severity, CVSS 10.0. EPSS: 36.6% chance of exploitation in the next 30 days.

An OS command injection vulnerability in lib/NSSDropoff.php in ZendTo 5.24-3 through 6.x before 6.10-7 allows unauthenticated remote attackers to execute arbitrary commands via shell metacharacters in the tmp_name parameter when dropping off a file via a POST /dropoff request.

Affected products

• Zend Zendto: from 5.24-3, before 6.10-7 (fixed in 6.10-7)

Published 2025-04-05. Last modified 2026-06-17.