CVE-2026-108725
Cheshire Cat AI core hasta la versión 2.0.23 contiene una vulnerabilidad de secuencias de comandos en sitios cruzados (XSS) almacenada en el complemento de cargas que permite a usuarios autenticados cargar archivos HTML mediante POST /uploads sin restricciones de tipo. Los atacantes pueden enviar la URL pública GET /uploads/{path} a una víctima con sesión iniciada, ejecutando script en el origen de la aplicación con la cookie access_token de la víctima, incluidos los administradores.
Traducción automática del texto original de NVD (en inglés).
CVSS
- Puntuación base
- 5.1
- Versión
- 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
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días
- 0.21 %
- Percentil entre todas las CVEs puntuadas
- 11
- Fecha de la puntuación
- 20/10/2026
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 access92 % - Impacto principal
T1059.007JavaScriptexecution90 % - Impacto secundario
T1078Valid Accountsstealth · persistence · privilege escalation · initial access75 %
XSS almacenado en plugin de uploads: atacante sube HTML malicioso (requiere autenticación) y víctima lo ejecuta al acceder a GET /uploads/{path}, exfiltrando cookies de sesión (access_token) con privilegios de administrador.
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-79
Referencias
Mostrar las 5 referencias
- https://github.com/cheshire-cat-ai/core
- https://github.com/cheshire-cat-ai/core/blob/c22731e7009ac89835b1d7b1cabc5989d998ec3e/src/cat/scaffold/plugins/uploads/endpoints.py#L28-L96
- https://hackmd.io/@haind03/cheshire-cat-uploads-stored-html-same-origin-xss
- https://www.vulncheck.com/advisories/cheshire-cat-ai-core-through-2.0.23-stored-xss-via-uploads-plugin
- https://hackmd.io/@haind03/cheshire-cat-uploads-stored-html-same-origin-xss
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-108725",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-108725",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-10-13T13:18:05.919586Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "disclosure@vulncheck.com",
"cvssData": {
"scope": "CHANGED",
"version": "3.1",
"baseScore": 5.4,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "LOW",
"confidentialityImpact": "LOW"
},
"impactScore": 2.7,
"exploitabilityScore": 2.3
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "disclosure@vulncheck.com",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 5.1,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"valueDensity": "NOT_DEFINED",
"vectorString": "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",
"exploitMaturity": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED",
"userInteraction": "PASSIVE",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "LOW",
"subIntegrityImpact": "LOW",
"vulnIntegrityImpact": "LOW",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "NONE",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "LOW",
"vulnConfidentialityImpact": "LOW",
"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"
}
}
]
},
"affected": [
{
"source": "disclosure@vulncheck.com",
"affectedData": [
{
"repo": "https://github.com/cheshire-cat-ai/core",
"vendor": "cheshire-cat-ai",
"product": "core",
"versions": [
{
"status": "affected",
"version": "0",
"versionType": "semver",
"lessThanOrEqual": "2.0.23"
}
],
"packageURL": "pkg:github/cheshire-cat-ai/core",
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-10-11T13:17:16.137",
"references": [
{
"url": "https://github.com/cheshire-cat-ai/core",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://github.com/cheshire-cat-ai/core/blob/c22731e7009ac89835b1d7b1cabc5989d998ec3e/src/cat/scaffold/plugins/uploads/endpoints.py#L28-L96",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://hackmd.io/@haind03/cheshire-cat-uploads-stored-html-same-origin-xss",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://www.vulncheck.com/advisories/cheshire-cat-ai-core-through-2.0.23-stored-xss-via-uploads-plugin",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://hackmd.io/@haind03/cheshire-cat-uploads-stored-html-same-origin-xss",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "disclosure@vulncheck.com",
"description": [
{
"lang": "en",
"value": "CWE-79"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Cheshire Cat AI core through 2.0.23 contains a stored cross-site scripting vulnerability in the uploads plugin that allows authenticated users to upload HTML files via POST /uploads without type restrictions. Attackers can send the public GET /uploads/{path} URL to a signed-in victim, executing script in the application origin with the victim's access_token cookie, including administrators."
}
],
"lastModified": "2026-10-16T19:18:44.867",
"sourceIdentifier": "disclosure@vulncheck.com"
}