{"id":"CVE-2026-110095","aliases":["GHSA-xhq7-xmqj-769h"],"title":"fast-uri vulnerable to improper path equivalence in relative reference normalization","summary":"fast-uri vulnerable to improper path equivalence in relative reference normalization","severity":"low","cvss":3.7,"cwe":["CWE-41","CWE-22"],"vendor":"fast-uri","product":"fast-uri","ecosystem":"npm","affected":["fast-uri < 2.4.8","fast-uri >= 3.0.0, < 3.1.9","fast-uri >= 4.0.0, < 4.2.3"],"patched":["fast-uri 2.4.8","fast-uri 3.1.9","fast-uri 4.2.3"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T21:39:38Z","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-xhq7-xmqj-769h","references":[{"url":"https://github.com/fastify/fast-uri/security/advisories/GHSA-xhq7-xmqj-769h"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-110095"},{"url":"https://github.com/fastify/fast-uri/commit/048bbd0a252971be86d6579f0dfc87f8de5b9c47"},{"url":"https://github.com/fastify/fast-uri/commit/52774a5c35df36b0bbe439cd4c12c3dc0e50e3b9"},{"url":"https://github.com/fastify/fast-uri/commit/7c19f8b97ec51f1f20b4e3d9d5820cb8d5176058"},{"url":"https://github.com/fastify/fast-uri/commit/9eb8759a9825c046f57f7f695f1944bc39b88abd"},{"url":"https://github.com/fastify/fast-uri/commit/acc5c5d60c4209571789496e1732468911c7e12a"},{"url":"https://github.com/fastify/fast-uri/commit/b110a3571c37dfcf9d1c72ce2e2e178c78d1a424"},{"url":"https://cna.openjsf.org/security-advisories.html"},{"url":"https://github.com/fastify/fast-uri/releases/tag/v2.4.8"},{"url":"https://github.com/fastify/fast-uri/releases/tag/v3.1.9"},{"url":"https://github.com/fastify/fast-uri/releases/tag/v4.2.3"},{"url":"https://github.com/advisories/GHSA-xhq7-xmqj-769h"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-110095.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-110095"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2556002"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-110095"}],"tags":["ghsa","npm","cve.org","csaf","vex","red-hat"],"epss":0.00289,"epssPercentile":0.21382,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-20T16:07:32.689199Z"},"ingestedAt":"2026-10-20T07:55:43.639Z","slug":"CVE-2026-110095","body":"## Overview\n\n### Impact\n\n`fast-uri`'s `normalize()` and `serialize()` apply RFC 3986 dot-segment removal (`remove_dot_segments`) to the path of a relative-path reference. RFC 3986 section 5.2.4 defines that algorithm only for the merged target path during resolution, not for the reference itself, so applied to the reference it drops leading `..` segments and can turn a document-relative reference into a root-relative one.\n\nFor example, `normalize('a/../b')` returns `/b` and `normalize('../x')` returns `x`, so `resolve(base, normalize(ref))` points at a different resource than `resolve(base, ref)`, and `equal()` treats distinct references as the same.\n\nApplications that normalize attacker-supplied or user-supplied relative references and then resolve them, or use them as cache, deduplication, or authorization keys, can have a reference escape its intended directory and point at a different resource.\n\n### Patches\n\nUpgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`.\n\n### Workarounds\n\nDo not normalize a relative reference before resolving it. Resolve it against the absolute base first, then normalize the absolute result.\n\n## Affected packages\n\n- `fast-uri < 2.4.8`\n- `fast-uri >= 3.0.0, < 3.1.9`\n- `fast-uri >= 4.0.0, < 4.2.3`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `fast-uri 2.4.8`\n- `fast-uri 3.1.9`\n- `fast-uri 4.2.3`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Cost Management On Premise, Cryostat 4, Migration Toolkit for Applications 8, Multicluster Engine for Kubernetes, Network Observability Operator, OpenShift Lightspeed, … · no fix planned: Red Hat Ansible Automation Platform 2, Red Hat Directory Server 11, Red Hat Directory Server 12, Red Hat Openshift Data Foundation 4, … · updated 2026-10-20 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-110095.json)","depth":"sunlit","depthScore":20,"depthScoreParts":{"impact":20.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}