VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 22 January 2026Ransomware use: unknown
Synacor Zimbra Collaboration Suite (ZCS)

CVE-2025-68645: Synacor Zimbra Collaboration Suite (ZCS) PHP Remote File Inclusion Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 22 Jan 2026, 31 days after the CVE record was published.

How likely is exploitation in the next 30 days?
48.9%

EPSS score, percentile 98.9 of all scored records

How severe?
8.8 High

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

CISA deadline 12 Feb 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.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Not stated. The CVE record gives vendor and product as “n/a” and the version as “unspecified”.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

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 due date for this action: 12 February 2026.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

Affected products and versions

The CVE record does not name affected products or versions: vendor and product are “n/a” and the version is “unspecified”.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

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.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2025-68645 to its Known Exploited Vulnerabilities (KEV) catalog on 22 Jan 2026.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 12 Feb 2026.
  • The CVE record was published on 22 Dec 2025, 31 days before it was added to KEV.
  • The CVE record carries a CVSS v3.1 base score of 8.8 (High), taken from CISA's enrichment of the record.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 48.9% (percentile 98.9), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

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.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

  • CWE-98: Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion')

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

DateEvent
22 Dec 2025CVE record published
22 Jan 2026Added to CISA KEV
12 Feb 2026CISA due date for the required action
26 Feb 2026CVE record last updated

References

More exploited Synacor vulnerabilities

  • CVE-2026-73570: Zimbra Collaboration Suite (ZCS) OS Command Injection Vulnerability (added 21 Aug 2026)
  • CVE-2025-48700: Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability (added 20 Apr 2026)
  • CVE-2025-66376: Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting Vulnerability (added 18 Mar 2026)
  • CVE-2020-7796: Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery Vulnerability (added 17 Feb 2026)
  • CVE-2025-27915: Synacor Zimbra Collaboration Suite (ZCS) Cross-site Scripting Vulnerability (added 7 Oct 2025)
  • CVE-2019-9621: Synacor Zimbra Collaboration Suite (ZCS) Server-Side Request Forgery (SSRF) Vulnerability (added 7 Jul 2025)