Vulnerability-Lookup

FKIE_CVE-2021-39169

Vulnerability from fkie_nvd - Published: 2021-08-27 13:15 - Updated: 2026-06-17 04:03

Severity

8.0 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
5.4 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Summary

Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading.

References

URL	Tags
security-advisories@github.com	https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99	Patch, Third Party Advisory
security-advisories@github.com	https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww	Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108	https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99	Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108	https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww	Patch, Third Party Advisory

Impacted products

	Vendor	Product	Version
	misskey	misskey	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "misskey",
          "vendor": "misskey-dev",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 12.51.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:misskey:misskey:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8E6D51FB-70AB-4EF8-B173-168D76D8338A",
              "versionEndExcluding": "12.51.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Misskey is a decentralized microblogging platform. In versions of Misskey prior to 12.51.0, malicious actors can use the web client built-in dialog to display a malicious string, leading to cross-site scripting (XSS). XSS could compromise the API request token. This issue has been fixed in version 12.51.0. There are no known workarounds aside from upgrading."
    },
    {
      "lang": "es",
      "value": "Misskey es una platamanera de microblogging descentralizada. En las versiones de Misskey anteriores a 12.51.0, unos actores maliciosos pueden usar el di\u00e1logo incorporado en el cliente web para mostrar una cadena maliciosa, conllevando a un ataque de tipo cross-site scripting (XSS). El ataque de  tipo XSS podr\u00eda comprometer el token de petici\u00f3n de la API. Este problema ha sido corregido en la versi\u00f3n 12.51.0. No se conocen soluciones aparte de la actualizaci\u00f3n."
    }
  ],
  "id": "CVE-2021-39169",
  "lastModified": "2026-06-17T04:03:14.330",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "LOW",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "NETWORK",
          "authentication": "SINGLE",
          "availabilityImpact": "NONE",
          "baseScore": 3.5,
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:N/AC:M/Au:S/C:N/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 6.8,
        "impactScore": 2.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.0,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.1,
        "impactScore": 5.9,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.4,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.3,
        "impactScore": 2.7,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2021-08-27T13:15:07.020",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

CVE-2021-39169 (GCVE-0-2021-39169)

Vulnerability from cvelistv5 – Published: 2021-08-27 12:40 – Updated: 2024-08-04 01:58

Title

XSS vulnerability using dialog

Summary

Severity

8 (High)


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

CWE

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

Assigner

GitHub_M CNA under the mitre root

CNA scorecard C 72/100 over 7614 records in the last 180 days details

References

2 references

URL	Tags
https://github.com/misskey-dev/misskey/security/a…	x_refsource_CONFIRM
https://github.com/misskey-dev/misskey/commit/ec2…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
misskey-dev	misskey	Affected: < 12.51.0

Show details on NVD website

JSON

To clipboard

{
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        "providerMetadata": {
          "dateUpdated": "2024-08-04T01:58:18.216Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
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        },
        "references": [
          {
            "tags": [
              "x_refsource_CONFIRM",
              "x_transferred"
            ],
            "url": "https://github.com/misskey-dev/misskey/security/advisories/GHSA-pmmv-jwqh-f5ww"
          },
          {
            "tags": [
              "x_refsource_MISC",
              "x_transferred"
            ],
            "url": "https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "misskey",
          "vendor": "misskey-dev",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 12.51.0"
            }
          ]
        }
      ],
      "descriptions": [
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
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            {
              "cweId": "CWE-79",
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            }
          ]
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      ],
      "providerMetadata": {
        "dateUpdated": "2021-08-27T12:40:09.000Z",
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      },
      "references": [
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          "url": "https://github.com/misskey-dev/misskey/commit/ec203f7f795766f76b55fecc9248168c1cdf6c99"
        }
      ],
      "source": {
        "advisory": "GHSA-pmmv-jwqh-f5ww",
        "discovery": "UNKNOWN"
      },
      "title": "XSS vulnerability using dialog",
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        },
        "affects": {
          "vendor": {
            "vendor_data": [
              {
                "product": {
                  "product_data": [
                    {
                      "product_name": "misskey",
                      "version": {
                        "version_data": [
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            }
          ]
        },
        "impact": {
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            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
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    "state": "PUBLISHED"
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}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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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.

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