CVE-2026-54240 libde265: Pixel accessor signed integer overflow causes heap OOB read/write
A crafted HEVC stream triggers an integer overflow in libde265, leading to heap out-of-bounds reads or writes that can cause crashes or code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-54240?
CVE-2026-54240 is a high-severity vulnerability in strukturag libde265, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
libde265 is an open source implementation of the h.265 video codec. Versions prior to 1.1.1 use signed 32-bit arithmetic to calculate pixel offsets, allowing a crafted HEVC stream with large image dimensions to trigger an integer overflow and cause out-of-bounds heap reads or writes, potentially disclosing data, corrupting memory, or crashing the decoder. Version 1.1.1 contains a patch.
Which versions are affected by CVE-2026-54240?
How do I fix CVE-2026-54240?
Upgrade to a fixed version.
Is CVE-2026-54240 being exploited?
There is no known exploitation of CVE-2026-54240 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2026-54240, BELL-CVE-2026-54240, DEBIAN-CVE-2026-54240, ECHO-48af-523d-62b5, GHSA-ccfw-29x7-rrx3, MINI-wrq7-4x2v-7g7h and 2 more.