CVE-2025-68645

Synacor Zimbra Collaboration Suite (ZCS): PHP Remote File Inclusion

As of , CVE-2025-68645 in Synacor Zimbra Collaboration Suite (ZCS) is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.

Exploited
Yes: CISA listed it on 22 January 2026
US federal deadline
12 February 202621 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.49Higher than 98% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
Vendor advice: wiki.zimbra.comLinks below, from CISA's entry.

What CISA says to do

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

CISA's required action

What the flaw is

Synacor Zimbra Collaboration Suite (ZCS) contains a PHP remote file inclusion vulnerability that could allow for remote attackers to craft requests to the /h/rest endpoint to influence internal request dispatching, allowing inclusion of arbitrary files from the WebRoot directory.

CISA's description

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.

The CVE record's description, from mitre

CVE published
22 December 2025
Assigned by
mitre
CVSS
8.8 High (CVSS 3.1, from CISA-ADP)
CWE-98
Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion')
CISA SSVC, exploitation
active
CISA SSVC, automatable
no
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Zimbra Collaboration Suite (ZCS): other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2026-73570OS Command InjectionSynacor Zimbra Collaboration Suite (ZCS)Patch nowForensic triage required by CISA0.72
CVE-2019-9621Server-Side Request Forgery (SSRF)Synacor Zimbra Collaboration Suite (ZCS)Patch this weekMetasploit module; EPSS 0.81; verified Exploit-DB entry0.81
CVE-2019-9670Improper Restriction of XML External Entity ReferenceSynacor Zimbra Collaboration Suite (ZCS)Patch this weekMetasploit module; EPSS 0.99; verified Exploit-DB entry0.99
CVE-2022-41352Arbitrary File UploadSynacor Zimbra Collaboration Suite (ZCS)Patch this weekRansomware use; Metasploit module; EPSS 0.950.95
CVE-2022-27925Arbitrary File UploadSynacor Zimbra Collaboration Suite (ZCS)Patch this weekRansomware use; Metasploit module; EPSS 0.990.99
CVE-2022-37042Authentication BypassSynacor Zimbra Collaboration Suite (ZCS)Patch this weekRansomware use; Metasploit module; EPSS 0.920.92
CVE-2023-34192Cross-Site Scripting (XSS)Synacor Zimbra Collaboration Suite (ZCS)Patch this weekEPSS 0.770.77
CVE-2024-45519Command ExecutionSynacor Zimbra Collaboration Suite (ZCS)Patch this weekEPSS 0.990.99
CVE-2022-27924Command InjectionSynacor Zimbra Collaboration Suite (ZCS)Patch this weekRansomware use; EPSS 0.940.94
CVE-2018-6882Cross-Site Scripting (XSS)Synacor Zimbra Collaboration Suite (ZCS)Patch this weekRansomware use0.30

All 17 entries for Zimbra Collaboration Suite (ZCS)

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