CVE-2026-32741
libheif has a heap buffer overflow in decode_mask_image()
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.
INFO
Published Date :
May 19, 2026, 9:16 p.m.
Last Modified :
May 19, 2026, 9:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-32741
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update libheif to version 1.22.0 or later.
- Apply patches for libheif to fix heap overflow.
- Validate file integrity before processing HEIF files.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-32741.
| URL | Resource |
|---|---|
| https://github.com/strukturag/libheif/releases/tag/v1.22.0 | |
| https://github.com/strukturag/libheif/security/advisories/GHSA-j3w5-7whq-p37q |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-32741 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-32741
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-32741 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-32741 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
May. 19, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H Added CWE CWE-122 Added Reference https://github.com/strukturag/libheif/releases/tag/v1.22.0 Added Reference https://github.com/strukturag/libheif/security/advisories/GHSA-j3w5-7whq-p37q