CVE-2026-63274: the document foundation libreoffice Out-of-bounds Read

Vulnerability summary

CVE-2026-63274 is a medium (CVSS 5.4) Out-of-bounds Read vulnerability in the document foundation libreoffice. EPSS estimates a 0.19% chance of exploitation in the next 30 days, higher than 7.7% of scored vulnerabilities.

Timeline

1. 22-09-2026
   PublishedVulnerability first disclosed.
2. 28-09-2026
   Last modifiedVulnerability information updated.

Description

LibreOffice Draw can import PDF documents. A heap buffer overflow existed when importing a stream object. The length of the stream was taken from the object's own dictionary and was not checked against the number of bytes actually present, so copying the stream read and wrote past the end of the buffer holding it. In fixed versions the declared length is clamped to the bytes actually read.

• CWE-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.
• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.