Vulnerability-Lookup

GHSA-XHQ7-XMQJ-769H

Vulnerability from github – Published: 2026-10-23 21:39 – Updated: 2026-10-23 21:39

Summary

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

Details

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.

Severity

3.7 (Low)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "fast-uri"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.4.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "fast-uri"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "fixed": "3.1.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "fast-uri"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.2.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-110095"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-41"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-23T21:39:34Z",
    "nvd_published_at": "2026-10-20T07:17:08Z",
    "severity": "LOW"
  },
  "details": "### Impact\n\n`fast-uri`\u0027s `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(\u0027a/../b\u0027)` returns `/b` and `normalize(\u0027../x\u0027)` 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.",
  "id": "GHSA-xhq7-xmqj-769h",
  "modified": "2026-10-23T21:39:34Z",
  "published": "2026-10-23T21:39:34Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/security/advisories/GHSA-xhq7-xmqj-769h"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110095"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/commit/048bbd0a252971be86d6579f0dfc87f8de5b9c47"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/commit/52774a5c35df36b0bbe439cd4c12c3dc0e50e3b9"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/commit/7c19f8b97ec51f1f20b4e3d9d5820cb8d5176058"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/commit/9eb8759a9825c046f57f7f695f1944bc39b88abd"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/commit/acc5c5d60c4209571789496e1732468911c7e12a"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/commit/b110a3571c37dfcf9d1c72ce2e2e178c78d1a424"
    },
    {
      "type": "WEB",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/fastify/fast-uri"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/releases/tag/v2.4.8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/releases/tag/v3.1.9"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fastify/fast-uri/releases/tag/v4.2.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "fast-uri vulnerable to improper path equivalence in relative reference normalization"
}

CVE-2026-110095 (GCVE-0-2026-110095)

Vulnerability from cvelistv5 – Published: 2026-10-20 06:56 – Updated: 2026-10-20 16:07

Title

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

Summary

fast-uri is a dependency-free RFC 3986 URI parser and serializer for Node.js. In versions before 2.4.8, from 3.0.0 through 3.1.8, and from 4.0.0 through 4.2.2, the normalize() and serialize() functions apply RFC 3986 dot-segment removal to the path of a relative-path reference, even though that algorithm is defined only for the merged target path during resolution, so a leading parent-directory segment can be dropped and a document-relative reference can become root-relative. An application that normalizes an attacker-supplied or user-supplied relative reference and then resolves it, or uses it as a cache, deduplication, or authorization key, can have the reference escape its intended directory and point at a different resource. The issue is fixed in fast-uri 2.4.8, 3.1.9, and 4.2.3, and users should upgrade to one of these versions or later. As a workaround, resolve a relative reference against its absolute base first and normalize the absolute result instead of normalizing the reference beforehand.

Severity

3.7 (Low)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-20 16:07 UTC

CWE

CWE-41 - Improper Resolution of Path Equivalence

Assigner

openjs CNA under the redhat root

CNA scorecard C 65/100 over 121 records in the last 180 days details

References

2 references

URL	Tags
https://github.com/fastify/fast-uri/security/advi…
https://cna.openjsf.org/security-advisories.html

Impacted products

1 product

Vendor	Product	Version
fast-uri	fast-uri	Affected: 0 , < 2.4.8 (semver) Unaffected: 2.4.8 (semver) Affected: 3.0.0 , < 3.1.9 (semver) Unaffected: 3.1.9 (semver) Affected: 4.0.0 , < 4.2.3 (semver) Unaffected: 4.2.3 (semver)

Credits

UlisesGascon mcollina zekth

Show details on NVD website

JSON

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Sightings

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