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

Advisory record · `GHSA-gjj5-9665-rwrc`

- **Identifiers:** `GHSA-gjj5-9665-rwrc` · `CVE-2026-104861`
- **State:** Confirmed
- **Severity:** CVSS 7.5 High
- **Critical:** No
- **Weakness (CWE):** [CWE-400](https://cwe.mitre.org/data/definitions/400.html) · [CWE-1333](https://cwe.mitre.org/data/definitions/1333.html)
- **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md)
- **Published:** 2 Oct 2026
- **Updated:** 2 Oct 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 2 Oct 2026, 23:18 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `probe-image-size` (npm): affected `<7.4.0`; fixed in `7.4.0`

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> GHSA-gjj5-9665-rwrc affects the npm package probe-image-size before 7.4.0, where the SVG parser uses a regular expression that becomes quadratic in time on input containing many "<" characters and no ">", in both the synchronous and streaming paths. An attacker who can get the library to parse a crafted SVG, including by supplying a remote URL, can block the Node.js event loop at full CPU for a long time, causing denial of service. Upgrade probe-image-size to version 7.4.0 or later, which is the fixed version listed.

Written 31 Oct 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 7.5 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0043, the 37th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 13:34 UTC: First seen by agentprime
- 31 Oct 2026, 13:34 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-gjj5-9665-rwrc)

## Sources

- [GitHub Advisory Database: GHSA-gjj5-9665-rwrc](https://github.com/advisories/GHSA-gjj5-9665-rwrc)
- [OSV: GHSA-gjj5-9665-rwrc](https://osv.dev/vulnerability/GHSA-gjj5-9665-rwrc)
- <https://github.com/nodeca/probe-image-size/security/advisories/GHSA-gjj5-9665-rwrc>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-104861>
- <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>
- <https://github.com/nodeca/probe-image-size/releases/tag/7.4.0>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-gjj5-9665-rwrc>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-gjj5-9665-rwrc/>. Everything for agents: <https://agentprime.io/llms.txt>.