CVE-2026-84384: Strukturag Libheif

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.2, crafted HEIF or AVIF mime metadata and unci image data can cause decompress_brotli() and do_inflate() to grow accumulated output without an effective size limit or MemoryHandle accounting. The brotli path has no output bound, while the zlib path checks only a small temporary buffer in a branch that valid streams do not reach, and overlapping icef units can decompress the same payload repeatedly. HeifContext::interpret_heif_file_images() processes multiple compressed metadata items during file opening, allowing a small file to consume unbounded memory and terminate the process. This issue is fixed in version 1.23.2.

Affected products

• Strukturag Libheif: from 1.19.0, before 1.23.2 (fixed in 1.23.2)

Published 2026-09-18. Last modified 2026-09-18.