A vulnerability (CVE-2026-4430, CVSS 7.8 HIGH) in LibreOffice involves improper handling of mismatched encryption salt parameters in crafted OOXML documents, which could lead to a crash or arbitrary code execution. Affected versions are LibreOffice 25.8.0.0 through 25.8.6.x and 26.2.0.0 through 26.2.2.x. The issue is fixed in LibreOffice versions 25.8.7.0 and 26.2.3.0.
Ubuntu Security Notices USN-8352-1 USN-8352-1: LibreOffice vulnerability Publication date 1 June 2026 Overview LibreOffice could be made to crash or run programs as your login if it opened a specially crafted file. Releases 26.04 LTS 25.10 Open side navigation Close side navigation Packages Details Update instructions References Related notices Packages libreoffice - Office productivity suite Details Duc Anh Nguyen discovered that LibreOffice incorrectly handled mismatched encryption salt parameters in crafted OOXML documents. An attacker could use this issue to cause LibreOffice to crash, resulting in a denial of service, or possibly execute arbitrary code. Duc Anh Nguyen discovered that LibreOffice incorrectly handled mismatched encryption salt parameters in crafted OOXML documents. An attacker could use this issue to cause LibreOffice to crash, resulting in a denial of service, or possibly execute arbitrary code. Update instructions This update uses a new upstream release, which includes additional bug fixes. In general, a standard system update will make all the necessary changes. Learn more about how to get the fixes. The problem can be corrected by updating your system to the following package versions: Ubuntu Release Package Version 26.04 LTS resolute libreoffice – 4:26.2.3.2-0ubuntu0.26.04.1 25.10 questing libreoffice – 4:25.8.7-0ubuntu0.25.10.1 Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. Get Ubuntu Pro References CVE-2026-4430 CVE-2026-4430 Related notices USN-8340-1 USN-8340-1