CVE-2025-24963 is a medium-severity (CVSS 5.9) Path Traversal vulnerability in @vitest/browser. A fix is available for @vitest/browser — see the affected versions and patch details below.
Browser mode serves arbitrary files in vitest
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-24963.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@vitest/browsernpmDescription
Summary
__screenshot-error handler on the browser mode HTTP server that responds any file on the file system. Especially if the server is exposed on the network by browser.api.host: true, an attacker can send a request to that handler from remote to get the content of arbitrary files.
Details
This __screenshot-error handler on the browser mode HTTP server responds any file on the file system.
https://github.com/vitest-dev/vitest/blob/f17918a79969d27a415f70431e08a9445b051e45/packages/browser/src/node/plugin.ts#L88-L130
This code was added by https://github.com/vitest-dev/vitest/commit/2d62051f13b4b0939b2f7e94e88006d830dc4d1f.
PoC
- Create a directory and change the current directory to that directory
- Run
npx vitest init browser - Run
npm run test:browser - Run
curl http://localhost:63315/__screenshot-error?file=/path/to/any/file
Impact
Users explicitly exposing the browser mode server to the network by browser.api.host: true may get any files exposed.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @vitest/browser | ≥ 2.0.4&&< 2.1.9 | 2.1.9npm install @vitest/browser@2.1.9 |
| 📦npm | @vitest/browser | ≥ 3.0.0&&< 3.0.4 | 3.0.4npm install @vitest/browser@3.0.4 |
Affected Products
vitestvitest.devDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @vitest/browser, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @vitest/browser to 2.1.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-24963 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
How to detect CVE-2025-24963
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2025-24963 -u https://target- Template
- Vitest Browser Mode - Local File Read
- Severity
- medium
- Impact
- Attackers can read arbitrary files from the file system when the browser mode server is exposed to the network, potentially exposing source code, configuration files, and sensitive credentials.
- Remediation
- Upgrade to Vitest version 2.1.9, 3.0.4 or later that addresses the __screenshot-error handler vulnerability.
Template by ProjectDiscovery nuclei-templates (iamnoooob, rootxharsh, pdresearch), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2025-24963 in your dependencies?
Find it across npm, including transitive dependencies.