ZCS 10.0-10.1 Webmail Classic LFI via RestFilter /h/rest
CVE-2025-68645 Published on December 22, 2025
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.
Known Exploited Vulnerability
This Synacor Zimbra Collaboration Suite (ZCS) PHP Remote File Inclusion Vulnerability is part of CISA's list of Known Exploited Vulnerabilities. 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.
The following remediation steps are recommended / required by February 12, 2026: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vulnerability Analysis
CVE-2025-68645 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. This vulnerability is known to be actively exploited by threat actors. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
What is a Remote file include Vulnerability?
The PHP application receives input from an upstream component, but it does not restrict or incorrectly restricts the input before its usage in "require," "include," or similar functions. In certain versions and configurations of PHP, this can allow an attacker to specify a URL to a remote location from which the software will obtain the code to execute. In other cases in association with path traversal, the attacker can specify a local file that may contain executable statements that can be parsed by PHP.
CVE-2025-68645 has been classified to as a Remote file include vulnerability or weakness.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.