image-size vulnerability

image-size through 2.0.2 contains a denial of service vulnerability that allows remote attackers to permanently block the Node.js event loop by supplying a specially crafted ICNS image buffer. Attackers can craft an ICNS buffer containing valid magic bytes and a zero-valued entry length field to trigger an infinite loop in the ICNS parser, as the offset is never incremented when the entry length field is 0, causing the while loop condition to remain true indefinitely.

Published 10 Jun 2026Updated 12 Oct 202626 sources
CVSS 8.7 ✓ VERIFIED REFERENCE

What happened

image-size through 2.0.2 contains a denial of service vulnerability that allows remote attackers to permanently block the Node.js event loop by supplying a specially crafted ICNS image buffer. Attackers can craft an ICNS buffer containing valid magic bytes and a zero-valued entry length field to trigger an infinite loop in the ICNS parser, as the offset is never incremented when the entry length field is 0, causing the while loop condition to remain true indefinitely.

Affected versions

image-size: 1.1.0 through 1.2.1 (semver); 2.0.0 through 2.0.2 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

RepositoryAuthorFirst seenReference
joshua.huNVD reference2026-06-10Verified