CVE-2026-6045: the document foundation libreoffice Out-of-bounds Write

Vulnerability summary

CVE-2026-6045 is a medium (CVSS 5.4) Out-of-bounds Write vulnerability in the document foundation libreoffice. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 5.6% of scored vulnerabilities.

Timeline

1. 15-06-2026
   PublishedVulnerability first disclosed.
2. 21-10-2026
   Last modifiedVulnerability information updated.

Description

LibreOffice can import EMF+ graphics, which may be embedded in documents. A heap buffer overflow existed when importing an EMF+ gradient brush. The number of gradient blend points was read from the file and used to compute an allocation size, but that multiplication could overflow, so a small buffer was allocated and then filled as if it were large, writing past its end. In fixed versions the blend-point count is checked against the data actually available before allocating.

• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
• CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.