# CVE-2025-71329: image-size 2.0.2 Denial of Service via Infinite Loop in JXL/HEIF Parser

Status: published. Published: 2026-06-10. Updated: 2026-11-08.

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 image buffer with a zero-valued size field in a recognized box-type. Attackers can trigger an infinite loop in the JXL or HEIF image parsers by providing a crafted image containing a box with a size of zero, causing the offset to never advance and permanently hanging the application.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://web.archive.org/web/20260224152152/https://github.com/image-size/image-size/pull/439

## Affected products and versions

- image-size / image-size (image-size): ≥ 1.1.0; ≤ 1.2.1 (affected, semver); ≥ 2.0.0; ≤ 2.0.2 (affected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 8.7 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 0.43% as of 2026-11-08; percentile 37.51%

- SSVC: exploitation poc; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-835

## Exploit evidence

- exploit: https://joshua.hu/image-size-infinite-loop-dos-vulnerabilities (CNA: VulnCheck)

## References

- https://joshua.hu/image-size-infinite-loop-dos-vulnerabilities (CNA: VulnCheck; technical-description, exploit)

- https://web.archive.org/web/20260224152152/https://github.com/image-size/image-size/pull/439 (CNA: VulnCheck; issue-tracking, patch)

- https://www.vulncheck.com/advisories/image-size-denial-of-service-via-infinite-loop-in-jxl-heif-parser (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2025-71329; retrieved 2026-11-08; source updated 2026-11-08

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-71329; retrieved 2026-11-08; source updated Not reported

Revision: 57814058a0643d83896aa6d84e7675de30d6933ae6f2d7b7e31486ce8c13ccb1

Canonical: https://y2.dev/cve/CVE-2025-71329

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.