CVE-2026-103439
Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in The Wikimedia Foundation MediaWiki Wikbase extension allows Cross-Site Scripting (XSS).
This issue affects MediaWiki Wikbase extension: 1.46, 1.45, and 1.43.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/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:N/AU:Y/R:U/V:D/RE:M/U:Amber
- Puntuación base: 0.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.11%
- Percentil entre todas las CVEs puntuadas: 1
- Fecha de la puntuación: 6/10/2026
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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1189Drive-by Compromiseinitial access85 % - Impacto principal
T1059.007JavaScriptexecution75 %
XSS en Wikbase (CWE-80) explotable sin privilegios reales mediante navegación web; impacto en ejecución de scripts en cliente.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-80
Referencias
JSON original (NVD)
Mostrar
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"id": "CVE-2026-103439",
"cveTags": [],
"metrics": {
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{
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"ssvcData": {
"id": "CVE-2026-103439",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
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"version": "2.0.3",
"timestamp": "2026-09-30T18:12:13.696391Z"
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"valueDensity": "DIFFUSE",
"vectorString": "CVSS:4.0/AV:L/AC:H/AT:P/PR:H/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/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:N/AU:Y/R:U/V:D/RE:M/U:Amber",
"exploitMaturity": "PROOF_OF_CONCEPT",
"providerUrgency": "AMBER",
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"vulnIntegrityImpact": "LOW",
"integrityRequirement": "NOT_DEFINED",
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"availabilityRequirement": "NOT_DEFINED",
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"affected": [
{
"source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc",
"affectedData": [
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"repo": "https://gerrit.wikimedia.org/r/mediawiki/extensions/Wikibase",
"vendor": "The Wikimedia Foundation",
"product": "MediaWiki Wikbase extension",
"versions": [
{
"status": "affected",
"version": "1.46"
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{
"status": "affected",
"version": "1.45"
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{
"status": "affected",
"version": "1.43"
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"defaultStatus": "unaffected"
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"published": "2026-09-30T18:18:16.590",
"references": [
{
"url": "https://gerrit.wikimedia.org/r/q/Ie7a35b211565148e0cae437a4a8c41633b81f1b3",
"source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc"
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{
"url": "https://phabricator.wikimedia.org/T182213",
"source": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc"
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"vulnStatus": "Awaiting Analysis",
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"description": [
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"descriptions": [
{
"lang": "en",
"value": "Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in The Wikimedia Foundation MediaWiki Wikbase extension allows Cross-Site Scripting (XSS).\n\nThis issue affects MediaWiki Wikbase extension: 1.46, 1.45, and 1.43."
}
],
"lastModified": "2026-09-30T21:17:08.833",
"sourceIdentifier": "c4f26cc8-17ff-4c99-b5e2-38fc1793eacc"
}