known ransomware use

Synacor Zimbra Collaboration Suite (ZCS) Arbitrary File Upload Vulnerability

Added to KEV
2022-08-11
Federal due date
2022-09-01
Vendor
Synacor
Product
Zimbra Collaboration Suite (ZCS)
EPSS
100.0th percentile (score 0.943, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2022-27925

CISA short description

Synacor Zimbra Collaboration Suite (ZCS) contains flaw in the mboximport functionality, allowing an authenticated attacker to upload arbitrary files to perform remote code execution. This vulnerability was chained with CVE-2022-37042 which allows for unauthenticated remote code execution.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.