CVE intelligence

CVE-2026-63273

Vulnerability intelligence

Published Sep 22, 2026Sources checked Oct 5, 2026

5.4MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-63273 and is rated Medium severity with a CVSS score of 5.4. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Ubuntu Security Notices guidance

Vendor revision: Oct 5, 2026

(CVE-2026-63279) It was discovered that LibreOffice incorrectly mitigated out-of-bounds writes via Graphite font actions.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-63273?

LibreOffice Draw can import PDF documents. A heap buffer overflow existed when importing an encrypted document. The length of the decryption key was taken from the document's own encryption dictionary and was used to fill a fixed size key buffer without being checked against it, so a length larger than that buffer wrote past its end. In fixed versions a declared key length larger than the buffer is rejected.

Source: NVD