CVE-2020-11535

9.8 criticalEPSS 2.3%

Critical (9.8) in onlyoffice document server. EPSS 2.3% chance of exploitation in the next 30 days.

An issue was discovered in ONLYOFFICE Document Server 5.5.0. An attacker can craft a malicious .docx file, and exploit XML injection to enter an attacker-controlled parameter into the x2t binary, to rewrite this binary and/or libxcb.so.1, and execute code on a victim's server.

Severity

CVSS 3.1

9.8 critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 2.3% chance of exploitation in the next 30 days; higher than 83% of CVEs (scores of 2026-10-31)
CWE: CWE-91
Published: 2020-04-15
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

onlyoffice:document_server

References

https://gist.github.com/andrewaeva/beb92d3d2f1c5672dbda5050e323f6a0
https://github.com/ONLYOFFICE/DocumentServer/blob/master/CHANGELOG.md#551
https://gist.github.com/andrewaeva/beb92d3d2f1c5672dbda5050e323f6a0
https://github.com/ONLYOFFICE/DocumentServer/blob/master/CHANGELOG.md#551

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