Vulnerability-Lookup

GHSA-C97M-VXHJ-P7J6

Vulnerability from github – Published: 2026-04-17 15:31 – Updated: 2026-04-18 01:02

Summary

goldmark vulnerable to Cross-site Scripting (XSS)

Details

Versions of the package github.com/yuin/goldmark/renderer/html before 1.7.17 are vulnerable to Cross-site Scripting (XSS) due to improper ordering of URL validation and normalization. The renderer validates link destinations using a prefix-based check (IsDangerousURL) before resolving HTML entities. This allows an attacker to bypass protocol filtering by encoding dangerous schemes using HTML5 named character references. For example, a payload such as javascript:alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL.

Severity

6.1 (Medium)


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

5.1 (Medium)


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

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/yuin/goldmark/renderer/html"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.7.17"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-5160"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-18T01:02:42Z",
    "nvd_published_at": "2026-04-15T06:16:13Z",
    "severity": "MODERATE"
  },
  "details": "Versions of the package github.com/yuin/goldmark/renderer/html before 1.7.17 are vulnerable to Cross-site Scripting (XSS) due to improper ordering of URL validation and normalization. The renderer validates link destinations using a prefix-based check (IsDangerousURL) before resolving HTML entities. This allows an attacker to bypass protocol filtering by encoding dangerous schemes using HTML5 named character references. For example, a payload such as javascript\u0026colon;alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL.",
  "id": "GHSA-c97m-vxhj-p7j6",
  "modified": "2026-04-18T01:02:42Z",
  "published": "2026-04-17T15:31:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-5160"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yuin/goldmark/commit/cb46bbc4eca29d55aa9721e04ad207c23ccc44f9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/yuin/goldmark"
    },
    {
      "type": "WEB",
      "url": "https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMYUINGOLDMARKRENDERERHTML-15838406"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "goldmark vulnerable to Cross-site Scripting (XSS)"
}

CVE-2026-5160 (GCVE-0-2026-5160)

Vulnerability from cvelistv5 – Published: 2026-04-15 05:00 – Updated: 2026-04-15 18:07

Summary

Versions of the package github.com/yuin/goldmark/renderer/html before 1.7.17 are vulnerable to Cross-site Scripting (XSS) due to improper ordering of URL validation and normalization. The renderer validates link destinations using a prefix-based check (IsDangerousURL) before resolving HTML entities. This allows an attacker to bypass protocol filtering by encoding dangerous schemes using HTML5 named character references. For example, a payload such as javascript&colon;alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL.

Severity

6.1 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-15 18:07 UTC

CWE

CWE-79 - Cross-site Scripting (XSS)

Assigner

snyk mitre root

References

2 references

URL	Tags
https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBC…
https://github.com/yuin/goldmark/commit/cb46bbc4e…

Impacted products

1 product

Vendor	Product	Version
n/a	github.com/yuin/goldmark/renderer/html	Affected: 0 , < 1.7.17 (semver)

Credits

Catalin Iovita (Snyk Security Research)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-5160",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-15T18:07:02.033634Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-15T18:07:10.025Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "github.com/yuin/goldmark/renderer/html",
          "vendor": "n/a",
          "versions": [
            {
              "lessThan": "1.7.17",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Catalin Iovita (Snyk Security Research)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Versions of the package github.com/yuin/goldmark/renderer/html before 1.7.17 are vulnerable to Cross-site Scripting (XSS) due to improper ordering of URL validation and normalization. The renderer validates link destinations using a prefix-based check (IsDangerousURL) before resolving HTML entities. This allows an attacker to bypass protocol filtering by encoding dangerous schemes using HTML5 named character references. For example, a payload such as javascript\u0026colon;alert(1) is not recognized as dangerous during validation, leading to arbitrary script execution in the context of applications that render the URL."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.1,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "exploitCodeMaturity": "NOT_DEFINED",
            "integrityImpact": "LOW",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
            "version": "3.1"
          },
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 5.1,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "userInteraction": "ACTIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "LOW"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-79",
              "description": "Cross-site Scripting (XSS)",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-15T05:00:01.655Z",
        "orgId": "bae035ff-b466-4ff4-94d0-fc9efd9e1730",
        "shortName": "snyk"
      },
      "references": [
        {
          "url": "https://security.snyk.io/vuln/SNYK-GOLANG-GITHUBCOMYUINGOLDMARKRENDERERHTML-15838406"
        },
        {
          "url": "https://github.com/yuin/goldmark/commit/cb46bbc4eca29d55aa9721e04ad207c23ccc44f9"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "bae035ff-b466-4ff4-94d0-fc9efd9e1730",
    "assignerShortName": "snyk",
    "cveId": "CVE-2026-5160",
    "datePublished": "2026-04-15T05:00:01.655Z",
    "dateReserved": "2026-03-30T14:14:48.647Z",
    "dateUpdated": "2026-04-15T18:07:10.025Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.