CVE-2026-84446: high-severity vulnerability in strukturag libheif
libheif: Sequence decode timing-table initialization allows non-terminating loops and unbounded memory, bypassing max_sequence_frames
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
libheif is a HEIF and AVIF file format decoder and encoder. Prior to 1.23.2, crafted HEIF sequence timing and edit-list data can make Track::init_sample_timing_table() compute a logical m_num_output_samples value that exceeds the uint32_t counters used by Track_Visual::decode_next_image_sample() and Track::get_next_sample_raw_data(). The resulting comparison can never reach the oversized output count, causing non-terminating decode or raw-sample loops and bypassing max_sequence_frames. The same sequence path repeatedly calls Box_stts::get_sample_duration() and allocates Chunk::m_sample_ranges and Track::m_presentation_timeline outside MemoryHandle accounting, allowing severe CPU and memory exhaustion from a small file. This issue is fixed in version 1.23.2.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
strukturag · libheifRelated CVEs — strukturag libheif
In the same product, most dangerous first.
CVE-2026-84383CRITICALlibheif: Heap buffer overflow in `scale_nearest_neighbor()` via duplicate Alpha planes from nested `iden`/`auxl` itemsEPSS 0.7%CVE-2026-32882HIGHlibheif: Heap Buffer OOB Read in overlay compositing due to wrong alpha strideEPSS 0.7%CVE-2026-32740HIGHlibheif: Heap-Buffer-Overflow Write in Grid Tile Chroma CompositingEPSS 0.7%CVE-2026-50142HIGHlibheif: unbounded heap allocation in HEIF sequence parser (stsz fixed-size mode missing bound check)EPSS 0.7%CVE-2026-62292HIGHlibheif: Out-of-bounds read in uncompressed unci tile range slicingEPSS 0.6%CVE-2026-84447HIGHlibheif: Derived-image indirect reference chains and tiled offsets bypass decode caching and MemoryHandle limits, causing CPU/memory amplification DoSEPSS 0.5%