CVE-2026-63274
libreoffice: heap buffer overflow in PDF import stream handling
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 22, 2026
Updated · November 2, 2026
Description
A flaw was found in LibreOffice. When a user imports a specially crafted PDF document with LibreOffice Draw, a heap-based buffer overflow can occur due to improper validation of the stream length. This issue can cause memory corruption, resulting in an application crash.
Statement
To exploit this issue, an attacker needs to convince a user to import a specially crafted PDF document. This flaw can cause memory corruption, resulting in an application crash. However, the possibility of arbitrary code execution is not discarded. For these reasons, this vulnerability has been rated with a moderate severity.
Default Red Hat Enterprise Linux security features, including SELinux enforcement, Address Space Layout Randomization (ASLR) and NX (No-Execute) stack protection, significantly increase the difficulty of achieving arbitrary code execution, limiting the impact of this vulnerability.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Do not import PDF documents from unknown or untrusted sources with LibreOffice Draw.
CVSS / CWE
CVSS 3.1 · 7.3CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
CWE-120 · Buffer Copy without Checking Size of Input