CVE-2021-22964
mediumpriority · track · 35EPSS 0.010 · 63 %ileEURUUSEPSS · scored 2026-10-24
A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double slash `//` followed by a domain: `http://localhost:3000//a//youtube.com/%2e%2e%2f%2e%2e`.A DOS vulnerability is possible if the URL contains invalid characters `curl --path-as-is "http://localhost:3000//^/.."`The issue shows up on all the `fastify-static` applications that set `redirect: true` option. By default, it is `false`.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–8.8
weaknesses
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affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-pgh6-m65r-2rhqDOS and Open Redirect with user input2021-10-12ghsa · osvUS
### Impact A redirect vulnerability in the `fastify-static` module allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double slash `//` followed by a domain: `http://localhost:3000//a//youtube.com/%2e%2e%2f%2e%2e`. A DOS vulnerability is possible if the URL contains invalid characters `curl --path-as-is "http://localhost:3000//^/.."` The issue shows up on all the `fastify-static` applications that set `redirect: true` option. By default, it is `false`. ### Patches The issue has been patched in `fastify-static@4.4.1` ### Workarounds If updating is not an option, you can sanitize the input URLs using the [`rewriteUrl`](https://www.fastify.io/docs/latest/Server/#rewriteurl) server option. ### References + Bug founder: drstrnegth + [hackerone Report](https://hackerone.com/reports/1361804) ### For more information If you have any questions or comments about this advisory: * Open an issue in [fastify-static](https://github.com/fastify/fastify-static) * Contact the [security team](https://github.com/fastify/fastify/blob/main/SECURITY.md#the-fastify-security-team)
also known as (4)
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sources
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references (4)
External citations — patches, advisories, analysis.
- https://github.com/fastify/fastify。Patchcnnvd
- https://hackerone.com/reports/1361804cnnvd
- https://hackerone.com/reports/1361804enisa_euvd
- https://hackerone.com/reports/1361804ExploitIssue TrackingPatchThird Party Advisorynvd
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