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TI-2026-36912 Aliases CVE-2026-50142

libheif: unbounded heap allocation in HEIF sequence parser (stsz fixed-size mode missing bound check)

Priority MEDIUM 40CWE-190Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-190 and the CVSS impact.

Summary

libheif is a HEIF and AVIF file format decoder and encoder. From 1.19.0 until 1.23.0, a crafted HEIF sequence accepted by heif_context_read_from_memory() with the msf1 sequence brand can cause unbounded heap allocation. In libheif/sequences/seq_boxes.cc, Box_stsz::parse() applies max_sequence_frames only to variable-size samples, so fixed-size mode accepts an attacker-controlled sample_count without a bound. In libheif/sequences/track.cc, Track::load() also adds current_sample_idx and samples_per_chunk in 32-bit arithmetic, allowing the consistency check to be bypassed by wraparound. The resulting values reach the Chunk::Chunk() allocation path, which can consume gigabytes of memory and crash or stall the process through memory exhaustion. This issue is fixed in version 1.23.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00655 51st percentileScored 2026-11-07
Fix Fixed libheif (strukturag): 1.23.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
strukturaglibheif1.19.0 to before 1.23.01.23.0Patch availableCNA
  • libheif Vendorstrukturag Affected 1.19.0 to before 1.23.0 Fixed in 1.23.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:struktur:libheif:*:*:*:*:*:*:*:*——strukturag
  • cpe:2.3:a:struktur:libheif:*:*:*:*:*:*:*:* Versions — — ·strukturag

Remediation

  • Fix · CNA libheif (strukturag) Fixed in 1.23.0

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-50142
  2. 2026-10-13 EPSS moved to the 50th–90th percentile

References

  • TI-2026-57994 libheif: Heap buffer overflow in `scale_nearest_neighbor()` via duplicate Alpha planes from nested `iden`/`auxl` items CVSS 3.1CRITICAL 9.8
  • TI-2026-25594 NULL Pointer Dereference in libde265 CVSS 4.0HIGH 8.7
  • TI-2023-27026 Libde265 v1.0.14 was discovered to contain a global buffer overflow vulnerability in the… CVSS 3.1HIGH 8.8
  • TI-2023-27020 libheif v1.17.5 was discovered to contain a segmentation violation via the function… CVSS 3.1HIGH 8.8
  • TI-2026-58037 Resource allocation without limits in strukturag libheif CVSS 3.1HIGH 7.5
  • TI-2026-57995 libheif: brotli/zlib decompression paths lack output-size limits, allowing decompression-bomb OOM/DoS CVSS 3.1HIGH 7.5
See all 113 →

Sources