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TI-2026-25233 Aliases CVE-2026-32741

libheif has a heap buffer overflow in decode_mask_image()

Priority MEDIUM 64CWE-122Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

libheif is a HEIF and AVIF file format decoder and encoder. Versions 1.21.2 and below contain a heap buffer overflow in MaskImageCodec::decode_mask_image(). When decoding a HEIF file containing a mask image (mski), the function copies the full iloc extent data into a pixel buffer using memcpy(dst, data.data(), data.size()). The copy length data.size() is determined by the iloc extent in the file (attacker-controlled), while the destination buffer is sized based on the declared image dimensions. Because no upper-bound check exists on the data length, a crafted file whose iloc extent exceeds the pixel buffer allocation overflows the heap. The vulnerable single-memcpy branch is reached when the mskC property specifies bits_per_pixel = 8 and the ispe property declares an even width ≥ 64 (so that stride == width), with no changes to default security limits or external codec plugins required. This issue has been fixed in version 1.22.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00343 28th percentileScored 2026-11-07
Fix Fixed libheif (strukturag): 1.22.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
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
strukturaglibheifbefore 1.22.01.22.0Patch availableCNA
  • libheif Vendorstrukturag Affected before 1.22.0 Fixed in 1.22.0 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 1.22.0

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat Enterprise Linux 10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-32741

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