libheif has a heap buffer overflow in decode_mask_image()
Summary
| CVE | CVE-2026-32741 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-19 21:16:42 UTC |
| Updated | 2026-05-20 17:16:21 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v3.1 7.1 HIGH from [email protected]
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
EPSS: 0.000370000 probability, percentile 0.112190000 (date 2026-05-27)
Problem Types: CWE-122 | CWE-122 CWE-122: Heap-based Buffer Overflow
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H |
| 3.1 | CNA | DECLARED | 7.1 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
RequiredScope
UnchangedConfidentiality
NoneIntegrity
LowAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Strukturag | Libheif | affected < 1.22.0 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/strukturag/libheif/security/advisories/GHSA-j3w5-7whq-p37q | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | github.com | |
| github.com/strukturag/libheif/releases/tag/v1.22.0 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.