fast-uri vulnerable to improper path equivalence in relative reference normalization

{
  "id": "bd1a3b6730e74e0e8146b28b65d920b7762df726bc92ee0415622e7f61bb0241",
  "url": "https://osv.dev/vulnerability/GHSA-xhq7-xmqj-769h",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "fast-uri vulnerable to improper path equivalence in relative reference normalization",
    "summary": "### Impact `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. For 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. Applications 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. ### Patches Upgrade to `fast-uri` `2.4.8`, `3.1.9`, or `4.2.3`. ### Workarounds Do not normalize a relative reference before resolving it. Resolve it against the absolute base first, then normalize the absolute result.",
    "evidence": "osv:GHSA-xhq7-xmqj-769h",
    "products": [
      {
        "name": {
          "value": "fast-uri",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "2.4.8",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "fast-uri",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "3.1.9",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "fast-uri",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.2.3",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "low",
    "structured": {
      "id": "GHSA-xhq7-xmqj-769h",
      "aliases": [
        "CVE-2026-110095",
        "GHSA-xhq7-xmqj-769h"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "2.4.8"
                }
              ]
            }
          ],
          "package": {
            "name": "fast-uri",
            "purl": "pkg:npm/fast-uri",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-xhq7-xmqj-769h/GHSA-xhq7-xmqj-769h.json"
          }
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "3.0.0"
                },
                {
                  "fixed": "3.1.9"
                }
              ]
            }
          ],
          "package": {
            "name": "fast-uri",
            "purl": "pkg:npm/fast-uri",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-xhq7-xmqj-769h/GHSA-xhq7-xmqj-769h.json"
          }
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "4.0.0"
                },
                {
                  "fixed": "4.2.3"
                }
              ]
            }
          ],
          "package": {
            "name": "fast-uri",
            "purl": "pkg:npm/fast-uri",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-xhq7-xmqj-769h/GHSA-xhq7-xmqj-769h.json"
          }
        }
      ],
      "modified": "2026-10-23T21:45:04.902389903Z",
      "provider": "osv",
      "references": [
        "https://github.com/fastify/fast-uri/security/advisories/GHSA-xhq7-xmqj-769h",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-110095",
        "https://github.com/fastify/fast-uri/commit/048bbd0a252971be86d6579f0dfc87f8de5b9c47",
        "https://github.com/fastify/fast-uri/commit/52774a5c35df36b0bbe439cd4c12c3dc0e50e3b9",
        "https://github.com/fastify/fast-uri/commit/7c19f8b97ec51f1f20b4e3d9d5820cb8d5176058",
        "https://github.com/fastify/fast-uri/commit/9eb8759a9825c046f57f7f695f1944bc39b88abd",
        "https://github.com/fastify/fast-uri/commit/acc5c5d60c4209571789496e1732468911c7e12a",
        "https://github.com/fastify/fast-uri/commit/b110a3571c37dfcf9d1c72ce2e2e178c78d1a424",
        "https://cna.openjsf.org/security-advisories.html",
        "https://github.com/fastify/fast-uri",
        "https://github.com/fastify/fast-uri/releases/tag/v2.4.8",
        "https://github.com/fastify/fast-uri/releases/tag/v3.1.9",
        "https://github.com/fastify/fast-uri/releases/tag/v4.2.3"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-41"
        ],
        "severity": "LOW",
        "github_reviewed": true,
        "nvd_published_at": "2026-10-20T07:17:08Z",
        "github_reviewed_at": "2026-10-23T21:39:34Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-110095",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 427042,
  "published_at": "2026-10-23T21:39:34+00:00"
}