---
id: "CVE-2026-123615"
page: "https://infrastack.ai/live/CVE-2026-123615"
kind: "vulnerability"
aliases: ["CVE-2026-123615"]
title: "imgproxy: crafted ICO image corrupts heap and crashes the worker"
severity: "high"
cvss: 8.7
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["docker", "imgproxy", "package", "self-hosted"]
not_affected_if: ["ico-disabled", "trusted-sources-only"]
published_at: "2026-11-08T02:16:57+00:00"
first_seen_at: "2026-11-08T02:21:14+00:00"
updated_at: "2026-11-08T02:22:43+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123615", "first_seen_at": "2026-11-08T02:21:14+00:00"}]
exploit_sources: []
---

# imgproxy: crafted ICO image corrupts heap and crashes the worker

Link for people: https://infrastack.ai/live/CVE-2026-123615 (this .md is for agents)

imgproxy 3.3.0 before 4.0.17 reads and writes past a heap buffer when its ICO loader rebuilds a BMP header from an entry with a tiny declared data size. An unauthenticated remote attacker can send a crafted ICO image to corrupt heap metadata and crash the worker process.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the imgproxy version in use, for example `imgproxy version` or the Docker image tag
- Confirm whether the deployment accepts remote source images (`IMGPROXY_ALLOW_...` and source URL settings) so untrusted ICO files reach the loader

## Fix

- imgproxy: move to `4.0.17` or later (the fix is in 4.0.17 per the description; 3.3.0 and earlier 3.x affected)

## Timeline

- 2026-11-08T02:21:14+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123615

## Documents

- [advisory] Maintainer's advisory: github.com https://github.com/imgproxy/imgproxy/security/advisories/GHSA-494m-4556-wf5p
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/imgproxy-before-4.0.17-out-of-bounds-write-in-ico-loader

## From the sources

imgproxy 3.3.0 before 4.0.17 contains an out-of-bounds heap read and write in the ICO loader's BMP header reconstruction (vips_foreign_load_ico_header in vips/icoload.c) when an ICO entry declares a tiny data size, causing unvalidated header fields to be read and written past the allocated buffer. Unauthenticated remote attackers can supply a crafted ICO image to corrupt adjacent heap chunk metadata, triggering a glibc abort that crashes the worker.

---

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