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Apexward Pulse
Type Vulnerability

Synacor

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

1 sourceCVE-2025-68645

At a glance

High
Suggested 24-hour window, counted from the last update
ActiveConfirmed in-the-wild exploitation
Evidence-weighted, not popularity
Signal

Actively exploited in the wild — prioritise confirming exposure.

Why High

High rather than Critical: exposure is scored at a default because we cannot see your systems or suppliers. If you run or depend on Synacor Zimbra Collaboration Suite (ZCS), treat it as Critical.

Briefing

  • Do not treat uncorroborated claims as confirmed breaches.

Questions to ask IT

  • Do we run Synacor Zimbra Collaboration Suite (ZCS), and which versions?
  • Is any of it reachable from the internet?
  • Have we checked whether it has already been used against us?
  • If it is still not patched, what mitigation is in place, and what is holding the fix up?

Next steps

  1. Confirm exposure, mitigation status and any service interruption risk.

Summary

  • 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.
  • CVE-2025-68645 is listed in known-exploited catalogue (exploitation in the wild)
  • Authoritative catalogues report active exploitation of this vulnerability.

Why this matters in the UK

  • Known-exploited catalogue reports exploitation in the wild

Products and services involved

Pulse

Last checked 4d ago · Recheck overdue since 5 Nov 2026, 22:07 UK time · 3 quiet checks collapsed

Signal
21 Aug 2026, 04:42 UK time · 21 Aug

in the next 30 days first recorded at 34.4% (elevated likelihood signal, not confirmed exploitation).

Elevated — confirm exposure; this is a probability signal, not confirmed exploitation.

EscalationDe-escalationCritical / liveWhat these mean
Drag to pan · Ctrl / ⌘ + scroll or pinch to zoom6 events

2 quiet checks hidden.

Sources

How we know

Statements extracted from sources. Higher confidence means stronger corroboration.

  • ConfirmedHeadline90% confidence

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

  • ConfirmedSummary fact75% confidence

    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. Affects Synacor Zimbra Collaboration Suite (ZCS). Known ransomware campaign use: Unknown.

  • ConfirmedCVE identifier95% confidence

    Event involves CVE-2025-68645

  • ConfirmedKnown-exploited catalogue98% confidence

    CVE-2025-68645 is listed in known-exploited catalogue (exploitation in the wild)