CVE-2026-32741
Publication date 19 May 2026
Last updated 19 June 2026
Ubuntu priority
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libheif | 26.04 LTS resolute |
Fixed 1.21.2-3ubuntu0.1
|
| 25.10 questing |
Fixed 1.20.2-1ubuntu0.4
|
|
| 24.04 LTS noble |
Fixed 1.17.6-1ubuntu4.4
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Not affected
|
Severity score breakdown
CVSS version: CVSS v3.0
Base score
7.1 · High
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8454-1
- libheif vulnerabilities
- 18 June 2026