Vulnerability-Lookup

CVE-2026-93751 (GCVE-0-2026-93751)

Vulnerability from cvelistv5 – Published: 2026-09-18 17:51 – Updated: 2026-09-18 17:51

Title

uri-js through 4.4.1 Improper UTF-8 Decoding via pctDecChars

Summary

uri-js through 4.4.1 contains an improper UTF-8 decoding vulnerability in pctDecChars() that decodes invalid and overlong percent-encoded sequences into ASCII metacharacters. Attackers can craft percent-encoded payloads to bypass platform decoder validation and inject path traversal or CRLF sequences that downstream consumers process without filtering.

Severity

6.9 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

6.5 (Medium)


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

CWE

CWE-176 - Improper Handling of Unicode Encoding

Assigner

VulnCheck mitre root

References

4 references

URL	Tags
https://github.com/garycourt/uri-js/issues/106	issue-tracking
https://github.com/garycourt/uri-js	product
https://github.com/garycourt/uri-js/blob/a1acf730…	technical-description
https://www.vulncheck.com/advisories/uri-js-throu…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version	CPE status
garycourt	uri-js	Affected: 0 , ≤ 4.4.1 (semver) cpe:2.3:a:garycourt:uri-js::::::::

Date Public

2026-09-17 00:00

Credits

Wayde Shi (PayPal Cyber Security Team)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:npm/uri-js",
          "product": "uri-js",
          "vendor": "garycourt",
          "versions": [
            {
              "lessThanOrEqual": "4.4.1",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:garycourt:uri-js:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "4.4.1",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Wayde Shi (PayPal Cyber Security Team)"
        }
      ],
      "datePublic": "2026-09-17T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "uri-js through 4.4.1 contains an improper UTF-8 decoding vulnerability in pctDecChars() that decodes invalid and overlong percent-encoded sequences into ASCII metacharacters. Attackers can craft percent-encoded payloads to bypass platform decoder validation and inject path traversal or CRLF sequences that downstream consumers process without filtering."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.9,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
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            "vulnIntegrityImpact": "LOW"
          },
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        {
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            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-176",
              "description": "Improper Handling of Unicode Encoding",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-18T17:51:36.332Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "GitHub Issue #106",
          "tags": [
            "issue-tracking"
          ],
          "url": "https://github.com/garycourt/uri-js/issues/106"
        },
        {
          "tags": [
            "product"
          ],
          "url": "https://github.com/garycourt/uri-js"
        },
        {
          "name": "pctDecChars() masking bytes without continuation-byte validation",
          "tags": [
            "technical-description"
          ],
          "url": "https://github.com/garycourt/uri-js/blob/a1acf730b4bba3f1097c9f52e7d9d3aba8cdcaae/src/uri.ts#L103-L141"
        },
        {
          "name": "VulnCheck Advisory: uri-js through 4.4.1 Improper UTF-8 Decoding via pctDecChars",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/uri-js-through-4.4.1-improper-utf-8-decoding-via-pctdecchars"
        }
      ],
      "title": "uri-js through 4.4.1 Improper UTF-8 Decoding via pctDecChars",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-93751",
    "datePublished": "2026-09-18T17:51:36.332Z",
    "dateReserved": "2026-09-18T16:30:18.137Z",
    "dateUpdated": "2026-09-18T17:51:36.332Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-93751",
      "date": "2026-09-19",
      "epss": "0.00233",
      "percentile": "0.14496"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "packageURL": "pkg:npm/uri-js",
                "product": "uri-js",
                "vendor": "garycourt",
                "versions": [
                  {
                    "lessThanOrEqual": "4.4.1",
                    "status": "affected",
                    "version": "0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "disclosure@vulncheck.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "uri-js through 4.4.1 contains an improper UTF-8 decoding vulnerability in pctDecChars() that decodes invalid and overlong percent-encoded sequences into ASCII metacharacters. Attackers can craft percent-encoded payloads to bypass platform decoder validation and inject path traversal or CRLF sequences that downstream consumers process without filtering."
          }
        ],
        "id": "CVE-2026-93751",
        "lastModified": "2026-09-18T18:18:34.177",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 6.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 2.5,
              "source": "disclosure@vulncheck.com",
              "type": "Primary"
            }
          ],
          "cvssMetricV40": [
            {
              "cvssData": {
                "Automatable": "NOT_DEFINED",
                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "NETWORK",
                "availabilityRequirement": "NOT_DEFINED",
                "baseScore": 6.9,
                "baseSeverity": "MEDIUM",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "valueDensity": "NOT_DEFINED",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
                "version": "4.0",
                "vulnAvailabilityImpact": "NONE",
                "vulnConfidentialityImpact": "LOW",
                "vulnIntegrityImpact": "LOW",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
              },
              "source": "disclosure@vulncheck.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-09-18T18:18:34.177",
        "references": [
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://github.com/garycourt/uri-js"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://github.com/garycourt/uri-js/blob/a1acf730b4bba3f1097c9f52e7d9d3aba8cdcaae/src/uri.ts#L103-L141"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://github.com/garycourt/uri-js/issues/106"
          },
          {
            "source": "disclosure@vulncheck.com",
            "url": "https://www.vulncheck.com/advisories/uri-js-through-4.4.1-improper-utf-8-decoding-via-pctdecchars"
          }
        ],
        "sourceIdentifier": "disclosure@vulncheck.com",
        "vulnStatus": "Received",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-176"
              }
            ],
            "source": "disclosure@vulncheck.com",
            "type": "Primary"
          }
        ]
      }
    }
  }
}

GHSA-7G43-P94J-QR58

Vulnerability from github – Published: 2026-09-18 18:31 – Updated: 2026-09-18 18:31

Details

Severity

6.5 (Medium)


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

6.9 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-93751"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-176"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-18T18:18:34Z",
    "severity": "MODERATE"
  },
  "details": "uri-js through 4.4.1 contains an improper UTF-8 decoding vulnerability in pctDecChars() that decodes invalid and overlong percent-encoded sequences into ASCII metacharacters. Attackers can craft percent-encoded payloads to bypass platform decoder validation and inject path traversal or CRLF sequences that downstream consumers process without filtering.",
  "id": "GHSA-7g43-p94j-qr58",
  "modified": "2026-09-18T18:31:44Z",
  "published": "2026-09-18T18:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93751"
    },
    {
      "type": "WEB",
      "url": "https://github.com/garycourt/uri-js/issues/106"
    },
    {
      "type": "WEB",
      "url": "https://github.com/garycourt/uri-js"
    },
    {
      "type": "WEB",
      "url": "https://github.com/garycourt/uri-js/blob/a1acf730b4bba3f1097c9f52e7d9d3aba8cdcaae/src/uri.ts#L103-L141"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/uri-js-through-4.4.1-improper-utf-8-decoding-via-pctdecchars"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.