# CVE-2026-32882: libheif: Heap Buffer OOB Read in overlay compositing due to wrong alpha stride

> A crafted HEIF file can trigger a heap buffer over-read in libheif, causing crashes or leaking adjacent memory during image compositing.

- **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 19 May 2026
- **Updated:** 15 Jul 2026
- **Also known as:** BELL-CVE-2026-32882, DEBIAN-CVE-2026-32882, ECHO-480e-f2af-bd01, GHSA-hg7q-rjr2-8x46, ROOT-OS-DEBIAN-11-CVE-2026-32882, ROOT-OS-DEBIAN-12-CVE-2026-32882, UBUNTU-CVE-2026-32882

## What is CVE-2026-32882?

CVE-2026-32882 is a high-severity memory corruption vulnerability in strukturag libheif, published on 19 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

libheif is a HEIF and AVIF file format decoder and encoder. Versions 1.21.2 and prior contain a heap buffer over-read in HeifPixelImage::overlay() in libheif/pixelimage.cc. When compositing an overlay image (iovl) whose child image has a different bit depth for the alpha channel than for the color channels, the function indexes into the alpha plane using the color channel stride (in_stride) instead of the previously retrieved alpha_stride, causing reads past the end of the alpha buffer (up to 3,123 bytes for a 100×50 image with 10-bit color and 8-bit alpha). A crafted HEIF file can exploit this to cause a denial of service (crash) or potentially disclose adjacent heap memory through leaked bytes embedded in the decoded output pixels. This issue has been fixed in versionThis issue has been fixed in version 1.22.0.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-32882?


## How do I fix CVE-2026-32882?

Upgrade to a fixed version.

## Is CVE-2026-32882 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32882 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-32882 and fix it if it is affected.

What it is: CVE-2026-32882 is a high-severity memory corruption vulnerability in strukturag libheif, published on 19 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32882 exists.

Affected product: strukturag libheif. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-32882/ (Markdown: https://insights.sbomify.com/CVE-2026-32882/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-32882
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-32882
- OSV: https://osv.dev/vulnerability/CVE-2026-32882

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-32882/
Summaries are generated and may contain mistakes; the official description above is the record.