Vulnerability-Lookup

GHSA-C8X8-7FP4-3X9W

Vulnerability from github – Published: 2026-10-05 22:36 – Updated: 2026-10-05 22:36

Summary

ProseMirror has a XSS vulnerability in prosemirror-view's paste handling

Details

Impact

When a user pastes attacker-provided HTML into a ProseMirror editor component, this can cause attacker-controlled JavaScript code to run in the browser window containing the editor.

Patches

Version 1.42.3 adds validation that prevents this attack.

Workarounds

No known workarounds.

Severity

8.5 (High)


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

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JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "prosemirror-view"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.42.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-104847"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-05T22:36:06Z",
    "nvd_published_at": "2026-10-02T16:16:47Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nWhen a user pastes attacker-provided HTML into a ProseMirror editor component, this can cause attacker-controlled JavaScript code to run in the browser window containing the editor.\n\n### Patches\n\nVersion 1.42.3 adds validation that prevents this attack.\n\n### Workarounds\n\nNo known workarounds.",
  "id": "GHSA-c8x8-7fp4-3x9w",
  "modified": "2026-10-05T22:36:06Z",
  "published": "2026-10-05T22:36:06Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-104847"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ProseMirror/prosemirror-view/commit/20dc0a911a79f8fc6640dbbea5e7d68d3c4784b7"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ProseMirror/prosemirror-view/commit/2e91a612bbc1248e55b4f6061fc93fe459f977c1"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ProseMirror/prosemirror-view"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "ProseMirror has a XSS vulnerability in prosemirror-view\u0027s paste handling"
}

CVE-2026-104847 (GCVE-0-2026-104847)

Vulnerability from cvelistv5 – Published: 2026-10-02 16:02 – Updated: 2026-10-02 16:57

Title

ProseMirror: XSS vulnerability in prosemirror-view's paste handling

Summary

ProseMirror's view component renders and manages the editable browser interface for ProseMirror documents. Prior to 1.42.3, prosemirror-view paste handling accepts attacker-provided HTML whose clipboard slice context contains attributes that are not passed through schema attribute validation. When a user pastes the crafted HTML into an editor, the unvalidated context attributes can construct content that executes attacker-controlled JavaScript in the browser window containing the editor. This issue is fixed in version 1.42.3.

Severity

8.5 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-02 16:57 UTC

CWE

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

Assigner

GitHub_M mitre root Scorecard

References

3 references

URL	Tags
https://github.com/ProseMirror/prosemirror-view/s…	x_refsource_CONFIRM
https://github.com/ProseMirror/prosemirror-view/c…	x_refsource_MISC
https://github.com/ProseMirror/prosemirror-view/c…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
ProseMirror	prosemirror-view	Affected: < 1.42.3

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-104847",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-10-02T16:57:07.727132Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-10-02T16:57:44.659Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "prosemirror-view",
          "vendor": "ProseMirror",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.42.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "ProseMirror\u0027s view component renders and manages the editable browser interface for ProseMirror documents. Prior to 1.42.3, prosemirror-view paste handling accepts attacker-provided HTML whose clipboard slice context contains attributes that are not passed through schema attribute validation. When a user pastes the crafted HTML into an editor, the unvalidated context attributes can construct content that executes attacker-controlled JavaScript in the browser window containing the editor. This issue is fixed in version 1.42.3."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.5,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "ACTIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "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": "2026-10-02T16:02:42.475Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w"
        },
        {
          "name": "https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/ProseMirror/prosemirror-view/security/advisories/GHSA-c8x8-7fp4-3x9w"
        },
        {
          "name": "https://github.com/ProseMirror/prosemirror-view/commit/20dc0a911a79f8fc6640dbbea5e7d68d3c4784b7",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/ProseMirror/prosemirror-view/commit/20dc0a911a79f8fc6640dbbea5e7d68d3c4784b7"
        },
        {
          "name": "https://github.com/ProseMirror/prosemirror-view/commit/2e91a612bbc1248e55b4f6061fc93fe459f977c1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/ProseMirror/prosemirror-view/commit/2e91a612bbc1248e55b4f6061fc93fe459f977c1"
        }
      ],
      "source": {
        "advisory": "GHSA-c8x8-7fp4-3x9w",
        "discovery": "UNKNOWN"
      },
      "title": "ProseMirror: XSS vulnerability in prosemirror-view\u0027s paste handling"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-104847",
    "datePublished": "2026-10-02T16:02:42.475Z",
    "dateReserved": "2026-10-02T14:38:43.243Z",
    "dateUpdated": "2026-10-02T16:57:44.659Z",
    "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.

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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