CVE-2026-54240

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.

  • Published Sep 11, 2026
  • CVSS 7.4 high
  • 0.4% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

CVE-2026-54240 at the National Vulnerability Database