# CVE-2026-84370: SVGO: removeScripts allows executable links through namespace and control-character bypasses

> Attacker can execute script in victim's browser context via bypassed SVG link filtering in SVGO when removeScripts plugin is enabled.

- **Severity:** High 8.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 1 Sep 2026
- **Updated:** 4 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-84370, GHSA-w27v-7q3p-w38r, ROOT-APP-NPM-CVE-2026-84370

## What is CVE-2026-84370?

CVE-2026-84370 is a high-severity cross-site scripting vulnerability in svgo, published on 1 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

SVGO, short for SVG Optimizer, is a Node.js library and command-line application for optimizing SVG files. From version 1.0.0 until versions 2.8.4, 3.3.5, and 4.1.0, the opt-in removeScripts plugin, named removeScriptElement in versions 2 and 3, incompletely filters executable links in plugins/removeScripts.js and lib/svgo/tools.js. The plugin does not recognize namespace-prefixed SVG anchor elements such as svg:a with href or namespaced *:href values, and it does not remove ASCII tab, line-feed, or carriage-return characters before checking URL schemes. Browsers remove those characters before parsing a scheme, allowing an executable link to pass the plugin's check. When an application processes attacker-controlled SVG input and serves the result in an active browser context, a victim who activates the surviving link can execute script in the SVG's origin, expose data, modify content, or perform actions as the victim. This issue is fixed in versions 2.8.4, 3.3.5, and 4.1.0.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-184 (Incomplete List of Disallowed Inputs)

## Which versions are affected by CVE-2026-84370?

6 open source packages ship an affected version, including svgo.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `svgo` | npm | From 1.0.0 | 2.8.4 |
| `svgo` | npm | From 1.0.0 | 2.8.4 |
| `svgo` | npm | From 3.0.0 | 3.3.5 |
| `svgo` | npm | From 3.0.0 | 3.3.5 |
| `svgo` | npm | From 4.0.0 | 4.1.0 |
| `svgo` | npm | From 4.0.0 | 4.1.0 |

## How do I fix CVE-2026-84370?

Upgrade svgo to a fixed version for your release line: 2.8.4, 3.3.5 or 4.1.0.

## Is CVE-2026-84370 being exploited?

There is no known exploitation of CVE-2026-84370 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-84370 and fix it if it is affected.

What it is: CVE-2026-84370 is a high-severity cross-site scripting vulnerability in svgo, published on 1 Sep 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-84370 in the wild and no public exploit code.

Affected packages and fixed versions:
- svgo (npm): affected from 1.0.0; fixed in 2.8.4
- svgo (npm): affected from 1.0.0; fixed in 2.8.4
- svgo (npm): affected from 3.0.0; fixed in 3.3.5
- svgo (npm): affected from 3.0.0; fixed in 3.3.5
- svgo (npm): affected from 4.0.0; fixed in 4.1.0
- svgo (npm): affected from 4.0.0; fixed in 4.1.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-84370/ (Markdown: https://insights.sbomify.com/CVE-2026-84370/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-84370
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-84370
- OSV: https://osv.dev/vulnerability/CVE-2026-84370

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-84370/
Summaries are generated and may contain mistakes; the official description above is the record.