Actively exploited in the wild

Synacor Zimbra Collaboration Suite (ZCS) Command Injection Vulnerability

Synacor - Zimbra Collaboration Suite (ZCS) · Listed in the CISA KEV since 2022-08-04. This indicates confirmed attacks in production environments.

Required action: Apply updates per vendor instructions.

CVE-2022-27924

HighCVSS 7.5KEV

Published: 21/04/2022(UTC)Updated: 04/08/2026(UTC)Translated: 05/08/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Very high risk

85.40%

100th percentile - higher than 100% of all known CVEs

Summary

Zimbra Collaboration (ZCS) 8.8.15 and 9.0 allows an unauthenticated attacker to inject arbitrary memcache commands into a targeted instance. These memcache commands become unescaped, causing an overwrite of arbitrary cached entries.

Risk Assessment

The risk includes the possibility of manipulating cached data, which could lead to data integrity issues or further attacks on the system.

Recommendation

It is recommended to upgrade Zimbra Collaboration to a patched version and monitor logs for suspicious requests.

Original NVD description (English source)

Zimbra Collaboration (aka ZCS) 8.8.15 and 9.0 allows an unauthenticated attacker to inject arbitrary memcache commands into a targeted instance. These memcache commands becomes unescaped, causing an overwrite of arbitrary cached entries.