Libheif Heap Buffer Over-Read Vulnerability (CVE-2026-32882) Exposes Data, Causes DoS
The National Vulnerability Database has detailed CVE-2026-32882, a critical heap buffer over-read vulnerability affecting libheif, a library for decoding and encoding HEIF and AVIF image formats. Versions prior to 1.22.0 contain a flaw in the HeifPixelImage::overlay() function. This vulnerability arises when compositing an overlay image with differing alpha channel bit depths from its color channels. The function incorrectly uses the color channel stride instead of the alpha channel stride, leading to reads beyond the allocated alpha buffer. This can result in denial of service through crashes or potential information disclosure via leaked heap memory bytes embedded in output pixels, with the National Vulnerability Database noting reads of up to 3,123 bytes for specific image configurations.
What This Means For You
- If your organization utilizes applications that process HEIF or AVIF images via libheif, you must update to version 1.22.0 or later immediately. Attackers can exploit this vulnerability by tricking users into opening a crafted image file, leading to system instability or potential data leakage. Prioritize patching this library to mitigate DoS risks and prevent sensitive memory contents from being exfiltrated.
Related ATT&CK Techniques
🛡️ Detection Rules
2 rules · 6 SIEM formats2 detection rules auto-generated for this incident, mapped to MITRE ATT&CK. Sigma YAML is free — export to any SIEM format via the Intel Bot.
CVE-2026-32882 - Libheif Heap Buffer Over-Read in PixelImage::overlay
title: CVE-2026-32882 - Libheif Heap Buffer Over-Read in PixelImage::overlay
id: scw-2026-05-19-ai-1
status: experimental
level: high
description: |
Detects the potential exploitation of CVE-2026-32882 by identifying processes that load or interact with libheif libraries when processing .heif or .avif files, particularly when initiated by common image viewers or editors. This rule aims to catch the initial trigger of the vulnerability, which could lead to a DoS or memory disclosure.
author: SCW Feed Engine (AI-generated)
date: 2026-05-19
references:
- https://shimiscyberworld.com/posts/nvd-CVE-2026-32882/
tags:
- attack.execution
- attack.t1204.002
logsource:
category: process_creation
detection:
selection:
Image|contains:
- 'libheif'
CommandLine|contains:
- '.heif'
- '.avif'
ParentImage|contains:
- 'explorer.exe'
- 'acrord32.exe'
- 'acrord64.exe'
- 'previewhost.exe'
- 'photoshop.exe'
- 'gimp-2.10.exe'
condition: Image AND CommandLine AND ParentImage
falsepositives:
- Legitimate administrative activity
Source: Shimi's Cyber World · License & reuse
Indicators of Compromise
| ID | Type | Indicator |
|---|---|---|
| CVE-2026-32882 | Buffer Overflow | libheif versions 1.21.2 and prior |
| CVE-2026-32882 | Denial of Service | Heap buffer over-read in HeifPixelImage::overlay() in libheif/pixelimage.cc |
| CVE-2026-32882 | Information Disclosure | Heap buffer over-read in HeifPixelImage::overlay() in libheif/pixelimage.cc |
| CVE-2026-32882 | Buffer Overflow | Crafted HEIF file exploiting alpha channel bit depth mismatch |
Written by SCW Vulnerability Desk
Source & Attribution
| Source Platform | NVD |
| Channel | National Vulnerability Database |
| Published | May 20, 2026 at 00:16 UTC |
This content was AI-rewritten and enriched by Shimi's Cyber World based on the original source. All intellectual property rights remain with the original author.
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