Description
fast-uri decoded percent-encoded path separators and dot segments before applying dot-segment removal in its normalize() and equal() functions. Encoded path data was treated like real slashes and parent-directory references, so distinct URIs could collapse onto the same normalized path. Applications that normalize or compare attacker-controlled URLs to enforce path-based policy can be bypassed, with a path that appears confined under an allowed prefix normalizing to a different location. Versions <= 3.1.0 are affected. Update to 3.1.1 or later.
Affected products
openjsf: fast-uri
References10
- cna.openjsf.org/security-advisories.html Vendor Advisory
- github.com/fastify/fast-uri/security/advisories/GHSA-q3j6-qgpj-… Vendor Advisory
- access.redhat.com/errata/RHSA-2026:19238
- access.redhat.com/errata/RHSA-2026:20338
- access.redhat.com/errata/RHSA-2026:21338
- access.redhat.com/errata/RHSA-2026:24473
- access.redhat.com/errata/RHSA-2026:24766
- access.redhat.com/errata/RHSA-2026:24866
- access.redhat.com/errata/RHSA-2026:24977
- access.redhat.com/errata/RHSA-2026:25089
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 1% percentile: 51 · as of 13 November 2026
- CWE
- CWE-22
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