---
id: CVE-2026-123616
title: imgproxy 3.3.0 before 4.0.16 Memory Exhaustion DoS via ICO Loader
summary: >-
  imgproxy from 3.3.0 before 4.0.16 contains an unbounded memory allocation
  vulnerability in the ICO loader that fails to validate the data_size field.
  Attackers can supply a crafted 23-byte ICO file declaring a ~4GB data_size to
  trigger m…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-789
vendor: imgproxy
product: imgproxy
affected:
  - imgproxy >= 3.3.0 < 4.0.16
published: '2026-11-08'
updated: '2026-11-08'
sourceUpdated: '2026-11-08T01:38:40.389Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-123616'
references:
  - url: >-
      https://github.com/imgproxy/imgproxy/security/advisories/GHSA-mmq5-xm89-9pfg
    label: GitHub Security Advisory (GHSA-mmq5-xm89-9pfg)
  - url: >-
      https://www.vulncheck.com/advisories/imgproxy-3.3.0-before-4.0.16-memory-exhaustion-dos-via-ico-loader
    label: >-
      VulnCheck Advisory: imgproxy 3.3.0 before 4.0.16 Memory Exhaustion DoS via
      ICO Loader
tags:
  - cve.org
ingestedAt: '2026-11-08T02:43:18.638Z'
---

## Overview

imgproxy from 3.3.0 before 4.0.16 contains an unbounded memory allocation vulnerability in the ICO loader that fails to validate the data_size field. Attackers can supply a crafted 23-byte ICO file declaring a ~4GB data_size to trigger memory exhaustion and worker crashes without authentication.

## Affected

- `imgproxy >= 3.3.0 < 4.0.16`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.