CVE-2021-47836 (GCVE-0-2021-47836)
Vulnerability from cvelistv5 – Published: 2026-01-16 19:09 – Updated: 2026-05-25 23:41
VLAI
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
6.1 (Medium)
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
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
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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