CISA KEV · Known exploitedHigh

CVE-2025-68645

Synacor Zimbra Collaboration Suite (ZCS)

A Local File Inclusion (LFI) vulnerability exists in the Webmail Classic UI of Zimbra Collaboration (ZCS) 10.0 and 10.1 because of improper handling of user-supplied request parameters in the RestFilter servlet. An unauthenticated remote attacker can craft requests to the /h/rest endpoint to influence internal request dispatching, allowing inclusion of arbitrary files from the WebRoot directory.

CVSS: 8.8
EPSS: 31.8%
CISA KEV: Listed
Published: 2025.12.23

PRIORITY ASSESSMENT

Immediate review

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.

Known exploitationConfirmed by CISA KEV

Exploit probability31.8%

Technical severityCVSS 8.8

Vulnerability overview

Affected product and versions

Product: Synacor Zimbra Collaboration Suite (ZCS)
Affected versions: >= 10.0.0 < 10.0.18, >= 10.1.0 < 10.1.13
Fixed versions: 10.0.18, 10.1.13

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Due date: 2026.02.12

1
Identify
Confirm that Synacor Zimbra Collaboration Suite (ZCS) and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE: CWE-98
KEV added: 2026.01.22
Ransomware use: 미확인