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CVE-2025-27791

Collabora Online Vulnerable to Arbitrary File Write

No known exploitation. EPSS puts it in the 40th percentile. No fix published yet.

CVSS —Not scoredEPSS percentile40th0.5% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFixNone yetNo fix or workaround published

Published Updated Sources: CVE.org, NVD

NVD CVE.org

What to do

No fixed build or workaround is published yet. Limit exposure and watch for a patch.

  • CollaboraOnline onlineAffected: >= 24.04.1.1, < 24.04.13.1Upgrade to: not statedAffected: >= 23.05.0, < 23.05.19Upgrade to: not statedAffected: < 22.05.25Upgrade to: not statedStated by: CVE record

Versions as the sources state them. Full version matrix after sign-in

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

Collabora Online is a collaborative online office suite based on LibreOffice technology. In versions prior to 24.04.12.4, 23.05.19, and 22.05.25, there is a path traversal flaw in handling the CheckFileInfo BaseFileName field returned from WOPI servers. This allows for a file to be written anywhere the uid running Collabora Online can write, if such a response was supplied by a malicious WOPI server. By combining this flaw with a Time of Check, Time of Use DNS lookup issue with a WOPI server address under attacker control, it is possible to present such a response to be processed by a Collabora Online instance. This issue has been patched in versions 24.04.13.1, 23.05.19, and 22.05.25.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS40th
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.5% chance of exploitation activity in the next 30 days, which ranks it in the 40th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

5 events over 436 days, from the signal feeds we watch.

  1. OpenVAS check added
  2. Record updated
  3. Publishedweakness classified, att&ck mapped

Affected products

Technical detail

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

References in the record

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We'll flag the next CVE, public exploit or patch for Online, not every advisory.