High severity · published Oct 5, 2026
CVE-2026-63277
RCE via calcext:data-mappings, sql provider and jdbc connector
8.5
CVSS
0.3%
EPSS
No
On KEV
Description
LibreOffice Calc can link a cell range to an external data source, and the link is saved in the document. A document could name a Java database driver for such a link to be loaded from a remote location, so opening the document could run Java code from that location. In fixed versions an entry in a Java class path has to be a file URL.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 27% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
LibreOffice · The Document Foundation
26.2 before < 26.2.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-63277
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-63277
www.libreoffice.org
https://www.libreoffice.org/about-us/security/advisories/cve-2026-63277
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