CVE-2026-86644
A vulnerability was determined in star7th showdoc up to 3.9.1. This vulnerability affects unknown code of the file web_src/public/editor.md/editormd.js of the component API Page Save Endpoint. Executing a manipulation can lead to cross site scripting. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 3.9.2 is able to resolve this issue. This patch is called a8ea1520850b4242f395247f72e87e597506cef0. Upgrading the affected component is recommended. The vendor confirms: "The fix [...] sets Mermaid `securityLevel` to `strict`, disables `htmlLabels`, and sanitizes rendered SVG with DOMPurify."
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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
- Puntuación base: 2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.36%
- Percentil entre todas las CVEs puntuadas: 28
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-79, CWE-94
Referencias
- https://gist.github.com/saDL0w/36a72a076e9ab24408a3d27582e778b2
- https://github.com/star7th/showdoc/
- https://github.com/star7th/showdoc/commit/a8ea1520850b4242f395247f72e87e597506cef0
- https://github.com/star7th/showdoc/releases/tag/v3.9.2
- https://vuldb.com/cve/CVE-2026-86644
- https://vuldb.com/submit/906282
- https://vuldb.com/vuln/399755
- https://vuldb.com/vuln/399755/cti
JSON original (NVD)
Mostrar
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"role": "CISA Coordinator",
"options": [
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"version": "2.0.3",
"timestamp": "2026-09-08T15:42:51.554304Z"
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"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 8,
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}
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"cvssMetricV31": [
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"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N",
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"Safety": "NOT_DEFINED",
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"attackVector": "NETWORK",
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"valueDensity": "NOT_DEFINED",
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"exploitMaturity": "PROOF_OF_CONCEPT",
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"subIntegrityImpact": "NONE",
"vulnIntegrityImpact": "LOW",
"integrityRequirement": "NOT_DEFINED",
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"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "NONE",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"confidentialityRequirement": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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"affected": [
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"affectedData": [
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"modules": [
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],
"product": "showdoc",
"versions": [
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"version": "3.9.0"
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{
"status": "affected",
"version": "3.9.1"
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"version": "3.9.2"
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"published": "2026-09-08T14:17:35.087",
"references": [
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"url": "https://gist.github.com/saDL0w/36a72a076e9ab24408a3d27582e778b2",
"source": "cna@vuldb.com"
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{
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"source": "cna@vuldb.com"
},
{
"url": "https://vuldb.com/submit/906282",
"source": "cna@vuldb.com"
},
{
"url": "https://vuldb.com/vuln/399755",
"source": "cna@vuldb.com"
},
{
"url": "https://vuldb.com/vuln/399755/cti",
"source": "cna@vuldb.com"
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],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "cna@vuldb.com",
"description": [
{
"lang": "en",
"value": "CWE-79"
},
{
"lang": "en",
"value": "CWE-94"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A vulnerability was determined in star7th showdoc up to 3.9.1. This vulnerability affects unknown code of the file web_src/public/editor.md/editormd.js of the component API Page Save Endpoint. Executing a manipulation can lead to cross site scripting. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 3.9.2 is able to resolve this issue. This patch is called a8ea1520850b4242f395247f72e87e597506cef0. Upgrading the affected component is recommended. The vendor confirms: \"The fix [...] sets Mermaid `securityLevel` to `strict`, disables `htmlLabels`, and sanitizes rendered SVG with DOMPurify.\""
}
],
"lastModified": "2026-09-08T18:33:29.460",
"sourceIdentifier": "cna@vuldb.com"
}