CVE-2021-47840
Status: DeferredMedium (5.1)—
Moeditor 0.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload specially crafted markdown files with embedded JavaScript that execute when opened, potentially enabling remote code execution on the victim's system.
CVSS
- Version: 4.0
- Vector: 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
- Base score: 5.1
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.45%
- Percentile among all scored CVEs: 37
- Score date: 10/5/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.
CWEs
- CWE-79
References
Raw JSON (NVD)
Show
{
"id": "CVE-2021-47840",
"cveTags": [],
"metrics": {
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"timestamp": "2026-01-16T21:00:05.614613Z"
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"valueDensity": "NOT_DEFINED",
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"vulnerabilityResponseEffort": "NOT_DEFINED",
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"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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"affected": [
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"versions": [
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"published": "2026-01-16T19:16:09.700",
"references": [
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"url": "https://imgur.com/a/UdP4JaX",
"source": "disclosure@vulncheck.com"
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{
"url": "https://moeditor.js.org/",
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{
"url": "https://www.exploit-db.com/exploits/49830",
"source": "disclosure@vulncheck.com"
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{
"url": "https://www.vulncheck.com/advisories/moeditor-persistent-cross-site-scripting",
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{
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"vulnStatus": "Deferred",
"weaknesses": [
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"description": [
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"descriptions": [
{
"lang": "en",
"value": "Moeditor 0.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload specially crafted markdown files with embedded JavaScript that execute when opened, potentially enabling remote code execution on the victim's system."
},
{
"lang": "es",
"value": "Moeditor 0.2.0 contiene una vulnerabilidad de cross-site scripting persistente que permite a los atacantes almacenar cargas útiles maliciosas dentro de archivos markdown. Los atacantes pueden subir archivos markdown especialmente diseñados con JavaScript incrustado que se ejecutan al abrirse, lo que podría permitir la ejecución remota de código en el sistema de la víctima."
}
],
"lastModified": "2026-06-17T04:18:35.577",
"sourceIdentifier": "disclosure@vulncheck.com"
}