Vulnerability-Lookup

GHSA-RFVR-HV7Q-M46G

Vulnerability from github – Published: 2026-01-16 21:30 – Updated: 2026-01-16 21:30

Details

Markdownify 1.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload crafted markdown files with embedded scripts that execute when the file is opened, potentially enabling remote code execution.

Severity ?

7.2 (High)


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

5.1 (Medium)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47837"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-16T19:16:09Z",
    "severity": "MODERATE"
  },
  "details": "Markdownify 1.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload crafted markdown files with embedded scripts that execute when the file is opened, potentially enabling remote code execution.",
  "id": "GHSA-rfvr-hv7q-m46g",
  "modified": "2026-01-16T21:30:36Z",
  "published": "2026-01-16T21:30:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47837"
    },
    {
      "type": "WEB",
      "url": "https://github.com/amitmerchant1990/electron-markdownify"
    },
    {
      "type": "WEB",
      "url": "https://imgur.com/a/T4jBoiS"
    },
    {
      "type": "WEB",
      "url": "https://www.exploit-db.com/exploits/49835"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/markdownify-persistent-cross-site-scripting"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/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"
    }
  ]
}

CVE-2021-47837 (GCVE-0-2021-47837)

Vulnerability from cvelistv5 – Published: 2026-01-16 19:09 – Updated: 2026-01-16 21:09

Title

Markdownify 1.2.0 - Persistent Cross-Site Scripting

Summary

Severity ?

5.1 (Medium)


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

7.2 (High)


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

CWE

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

Assigner

VulnCheck

References

URL

Tags

	https://www.exploit-db.com/exploits/49835	exploit
	https://github.com/amitmerchant1990/electron-mark…	product
	https://imgur.com/a/T4jBoiS	exploit
	https://www.vulncheck.com/advisories/markdownify-…	third-party-advisory

Impacted products

	Vendor	Product	Version
	amitmerchant1990	Markdownify	Affected: 1.2.0

Credits

TaurusOmar

Show details on NVD website

JSON

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  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47837",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-16T21:00:35.892323Z",
                "version": "2.0.3"
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      "credits": [
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          "value": "TaurusOmar"
        }
      ],
      "datePublic": "2021-04-05T00:00:00.000Z",
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      "metrics": [
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            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
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            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
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      "references": [
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          "name": "ExploitDB-49835",
          "tags": [
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        },
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          "tags": [
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          ],
          "url": "https://github.com/amitmerchant1990/electron-markdownify"
        },
        {
          "name": "Proof of Concept Video",
          "tags": [
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          ],
          "url": "https://imgur.com/a/T4jBoiS"
        },
        {
          "name": "VulnCheck Advisory: Markdownify 1.2.0 - Persistent Cross-Site Scripting",
          "tags": [
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}

Sightings

Author	Source	Type	Date

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.

Action not permitted

GHSA-RFVR-HV7Q-M46G

CVE-2021-47837 (GCVE-0-2021-47837)

Tags

Sightings

Nomenclature