| Package | Affected versions | Patched versions |
|---|---|---|
| fast-uri | < 3.1.2 | 3.1.2 |
| fast-uri | ≥ 3.0.0, < 3.1.2< 2.4.1 | 3.1.22.4.1 |
fast-uri v3.1.1 and earlier decodes percent-encoded authority delimiters (%40 as @, %3A as :) inside the host component and serializes them back as raw characters. This changes the URI structure, turning a hostname into userinfo plus a different host.
For example, http://trusted.com%40evil.com/ normalizes to http://[email protected]/, which reparses as host evil.com with userinfo trusted.com.
Applications that normalize untrusted URLs before host allowlist checks, redirect validation, or outbound request routing can be steered to a different authority than the original URL appeared to contain.
Upgrade to fast-uri >= 3.1.2, or if you are in the v2.x release line, v2.4.1
None. Upgrade to the patched version.
Running one of these products? Scan your site to see whether it exposes a vulnerable version.
Scan my site free