Apache OpenOffice: Code execution via crafted document in Java integration
Summary
Apache OpenOffice up to and including version 4.1.16 contains a code execution flaw in its Java integration. A specially crafted document can execute arbitrary code, including code loaded from a remote source, when a user opens it. The attack requires that the user opens the file and that Java runtime integration is enabled.
Affected
- Apache OpenOffice 4.1.16 and earlier
Fixed in
- Apache OpenOffice 4.1.17. The vendor advisory still describes 4.1.17 as in the release candidate phase, while the project website reports the release as published.
Workaround
- Disable Java runtime integration: Tools > Options > OpenOffice > Java, untick "Use a Java runtime environment" (on macOS: OpenOffice > Preferences > OpenOffice > Java). The vendor states that this prevents the attack.
- Do not open untrusted documents, for example unexpected email attachments or downloads.
Exploitation
- No confirmed exploitation in the wild at the time of research; not listed in the CISA KEV catalog.
- Public proof-of-concept reports are conflicting; assume that one may exist.
- CISA SSVC assessment: exploitation none, not automatable, total technical impact.
Our recommendation
- Identify all OpenOffice installations and check for versions 4.1.16 or earlier (Help > About).
- Upgrade to Apache OpenOffice 4.1.17 from the official download page.
- Until the upgrade is done, disable Java runtime integration and block or quarantine untrusted attachments.
- If LibreOffice is also used, make sure it is updated to a fixed release as published by its vendor.
Public exploits
Links to third-party sites, not checked by us – exploit code can contain malware. Only use it in isolated test environments.
- Proof of concept on GitHub (1 repositories)
HORKimhab/CVE-2026-59265
Research sources
- Apache OpenOffice security advisory CVE-2026-59265 www.openoffice.org
- oss-security post (Openwall) www.openwall.com
- Fix commit 95923fd437e06edd38a4f0e139a27c755a6f3ba6 github.com
- Fix commit c699bed3f75e79bd64ddec9dec49f9e210eed281 github.com
- AOO 4.1.17 Release Notes cwiki.apache.org
- Apache OpenOffice download page www.openoffice.org
- The Hacker Wire: CVE-2026-59265 www.thehackerwire.com
- Cybersecurity Waala: Java code execution flaws in LibreOffice and OpenOffice cybersecuritywaala.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 22:43.
Original description (NVD)
A code execution issue in the Java integration in Apache OpenOffice v4.1.16 and earlier allows a crafted untrusted document to trigger executing arbitrary (even remote) code when opened by the user. This issue is expected to be fixed in version 4.1.17, which is in the release candidate phase. Until then, users can mitigate this issue by disabling Java runtime integration in the Preferences dialog. This prevents the attack. If this is not possible, or as an extra precaution, you can avoid opening open untrusted files entirely. Once 4.1.17 is released, upgrade to that version to fix the issue.
NVD references (5)
- https://github.com/apache/openoffice/commit/95923fd437e06edd38a4f0e139a27c755a6f3ba6.patch
- https://github.com/apache/openoffice/commit/c699bed3f75e79bd64ddec9dec49f9e210eed281.patch
- https://lists.apache.org/thread.html/svfdc1jtpqlw7mo6lgg9fthcmf754pl5
- http://www.openwall.com/lists/oss-security/2026/10/02/2
- http://www.openwall.com/lists/oss-security/2026/10/08/7
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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