known ransomware use

Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability

Added to KEV
2022-04-19
Federal due date
2022-05-10
Vendor
Synacor
Product
Zimbra Collaboration Suite (ZCS)
EPSS
99.0th percentile (score 0.770, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2018-6882

CISA short description

Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability that might allow remote attackers to inject arbitrary web script or HTML.

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.