Vulnerability-Lookup

Search criteria

Vendor

Product

Assigner

Sources

Sort by

Order

CVSS min

CVSS max

Apply ordering (override relevance)

CVE-2026-59923 (GCVE-0-2026-59923)

Vulnerability from cvelistv5 – Published: 2026-07-08 16:14 – Updated: 2026-07-08 16:41

Title

Mistune: XSS via percent-encoded javascript URI bypass in safe_url()

Summary

Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version 3.3.0.

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: poc Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/lepture/mistune/security/advis…	x_refsource_CONFIRM
https://github.com/lepture/mistune/commit/c7101fc…	x_refsource_MISC
https://github.com/lepture/mistune/releases/tag/v3.3.0	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
lepture	mistune	Affected: < 3.3.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-59923",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-08T16:41:40.162930Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-08T16:41:52.111Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/lepture/mistune/security/advisories/GHSA-8c25-4j27-2rv3"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "mistune",
          "vendor": "lepture",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.3.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, HTMLRenderer.safe_url() does not block percent-encoded javascript URIs, allowing attacker-supplied Markdown links or images to bypass URL protections and execute script in rendered HTML. This issue is fixed in version 3.3.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.1,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "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"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-79",
              "description": "CWE-79: Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-08T16:14:39.266Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/lepture/mistune/security/advisories/GHSA-8c25-4j27-2rv3",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/lepture/mistune/security/advisories/GHSA-8c25-4j27-2rv3"
        },
        {
          "name": "https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/lepture/mistune/commit/c7101fcbb6e8790e8e39157c5ca2238fc6dd6cbc"
        },
        {
          "name": "https://github.com/lepture/mistune/releases/tag/v3.3.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/lepture/mistune/releases/tag/v3.3.0"
        }
      ],
      "source": {
        "advisory": "GHSA-8c25-4j27-2rv3",
        "discovery": "UNKNOWN"
      },
      "title": "Mistune: XSS via percent-encoded javascript URI bypass in safe_url()"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-59923",
    "datePublished": "2026-07-08T16:14:39.266Z",
    "dateReserved": "2026-07-07T18:20:06.125Z",
    "dateUpdated": "2026-07-08T16:41:52.111Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

PYSEC-2026-2211

Vulnerability from pysec - Published: 2026-07-08 17:17 - Updated: 2026-07-13 05:49

Details