fast-uri vulnerable to host confusion via backslash authority introducer

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0038, the 32nd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the GitHub Advisory Database, published 3 Aug 2026. New records show when each source confirmed them.

Sources

• GitHub Advisory Database: GHSA-7p8r-x3mc-p8w7
• OSV: GHSA-7p8r-x3mc-p8w7
• github.com/fastify/fast-uri/security/advisories/GHSA-7p8r-x3mc-p8w7
• nvd.nist.gov/vuln/detail/CVE-2026-18446
• github.com/fastify/fast-uri/commit/f3c6c905f47831007490f466c5945012e905cc52
• cna.openjsf.org/security-advisories.html
• github.com/fastify/fast-uri
• github.com/fastify/fast-uri/releases/tag/v4.1.2

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.