CVE-2026-54240: strukturag libde265 Integer Overflow or Wraparound

Vulnerability summary

CVE-2026-54240 is a high (CVSS 7.4) Integer Overflow or Wraparound vulnerability in strukturag libde265. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 32% of scored vulnerabilities.

Timeline

1. 11-09-2026
   PublishedVulnerability first disclosed.
2. 14-09-2026
   Last modifiedVulnerability information updated.

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.

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