Vulnerability-Lookup

GHSA-GJ7M-5VCR-WH6X

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

Details

Markdown Explorer 0.1.1 contains a cross-site scripting vulnerability that allows attackers to inject malicious code through file uploads and editor inputs. Attackers can upload markdown files with embedded JavaScript payloads to execute remote commands and potentially gain system access.

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:N/VA:N/SC:L/SI:L/SA:N

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2021-47836"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-16T19:16:09Z",
    "severity": "MODERATE"
  },
  "details": "Markdown Explorer 0.1.1 contains a cross-site scripting vulnerability that allows attackers to inject malicious code through file uploads and editor inputs. Attackers can upload markdown files with embedded JavaScript payloads to execute remote commands and potentially gain system access.",
  "id": "GHSA-gj7m-5vcr-wh6x",
  "modified": "2026-01-16T21:30:36Z",
  "published": "2026-01-16T21:30:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47836"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jersou/markdown-explorer"
    },
    {
      "type": "WEB",
      "url": "https://imgur.com/a/w4bcPWs"
    },
    {
      "type": "WEB",
      "url": "https://www.exploit-db.com/exploits/49826"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/markdown-explorer-persistent-cross-site-scripting"
    }
  ],
  "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:N/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-2021-47836 (GCVE-0-2021-47836)

Vulnerability from cvelistv5 – Published: 2026-01-16 19:09 – Updated: 2026-05-25 23:41

Title

Markdown Explorer 0.1.1 - Persistent Cross-Site Scripting

Summary

Markdown Explorer 0.1.1 contains a cross-site scripting vulnerability that allows attackers to inject malicious code through file uploads and editor inputs. Attackers can upload markdown files with embedded JavaScript payloads that execute in the application's privileged renderer context, allowing code execution on the host.

Severity

5.1 (Medium)


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

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

VulnCheck

References

4 references

URL	Tags
https://www.exploit-db.com/exploits/49826	exploit
https://github.com/jersou/markdown-explorer	product
https://imgur.com/a/w4bcPWs	exploit
https://www.vulncheck.com/advisories/markdown-exp…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
jersou	Markdown Explorer	Affected: 0.1.1

Date Public

2021-04-05 00:00

Credits

TaurusOmar

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2021-47836",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-16T21:00:44.698156Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-01-16T21:10:01.232Z",
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        },
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          }
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    ],
    "cna": {
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          "product": "Markdown Explorer",
          "vendor": "jersou",
          "versions": [
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            }
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          "type": "finder",
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        }
      ],
      "metrics": [
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            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
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        },
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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.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-GJ7M-5VCR-WH6X

CVE-2021-47836 (GCVE-0-2021-47836)

Tags

Sightings

Nomenclature