CVE-2026-63274 Heap buffer overflow in PDF import stream handling
Heap buffer overflow in LibreOffice Draw PDF import allows attackers to execute arbitrary code or cause denial of service via malicious documents.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-63274?
CVE-2026-63274 is a medium-severity memory corruption vulnerability in The Document Foundation LibreOffice, published on 22 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official 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.
Which versions are affected by CVE-2026-63274?
How do I fix CVE-2026-63274?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-63274 being exploited?
There is no known exploitation of CVE-2026-63274 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-63274, ECHO-8494-a0dc-6b0c, GHSA-q9rh-47xp-mj2m, MINI-v329-wf69-59m2, UBUNTU-CVE-2026-63274.