CVE-2026-79786
Coroot's unauthenticated MCP OAuth dynamic client registration endpoint accepts any syntactically valid redirect URI without validation, allowing attackers to register clients pointing to attacker-controlled hosts. Attackers can send authorization URLs to signed-in users, capture their authorization codes upon consent approval, and exchange them for access tokens to hijack MCP sessions.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/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
- Puntuación base: 7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.27%
- Percentil entre todas las CVEs puntuadas: 18
- 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
T1203Exploitation for Client Executionexecution85 % - Impacto principal
T1078Valid Accountsstealth · persistence · privilege escalation · initial access80 % - Impacto secundario
T1550.001Application Access Tokenlateral movement75 %
UI:A (interacción del usuario) + AV:N (red) indica explotación en el cliente (T1203). El atacante captura códigos de autorización y tokens para hijackear sesiones, logrando acceso a cuentas (T1078) y uso de tokens robados (T1550.001).
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-601
Referencias
- https://github.com/coroot/coroot
- https://github.com/coroot/coroot/blob/v1.24.5/api/mcp_oauth.go
- https://github.com/coroot/coroot/issues/929
- https://www.vulncheck.com/advisories/coroot-1.20.2-through-1.24.5-unvalidated-redirect-uri-in-mcp-oauth-client-registration
- https://github.com/coroot/coroot/issues/929
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-79786",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-79786",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-08-28T22:32:54.593010Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "disclosure@vulncheck.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.1,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N",
"integrityImpact": "LOW",
"userInteraction": "REQUIRED",
"attackComplexity": "LOW",
"availabilityImpact": "NONE",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 4.2,
"exploitabilityScore": 2.8
}
],
"cvssMetricV40": [
{
"type": "Secondary",
"source": "disclosure@vulncheck.com",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 7,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/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": "ACTIVE",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"privilegesRequired": "NONE",
"subIntegrityImpact": "NONE",
"vulnIntegrityImpact": "LOW",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"vulnAvailabilityImpact": "NONE",
"availabilityRequirement": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"subConfidentialityImpact": "NONE",
"vulnConfidentialityImpact": "HIGH",
"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/coroot/coroot",
"vendor": "coroot",
"product": "coroot",
"versions": [
{
"status": "affected",
"version": "1.20.2",
"versionType": "semver",
"lessThanOrEqual": "1.24.5"
}
],
"packageURL": "pkg:golang/github.com/coroot/coroot",
"collectionURL": "https://github.com/coroot/coroot",
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-08-25T19:16:54.750",
"references": [
{
"url": "https://github.com/coroot/coroot",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://github.com/coroot/coroot/blob/v1.24.5/api/mcp_oauth.go",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://github.com/coroot/coroot/issues/929",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://www.vulncheck.com/advisories/coroot-1.20.2-through-1.24.5-unvalidated-redirect-uri-in-mcp-oauth-client-registration",
"source": "disclosure@vulncheck.com"
},
{
"url": "https://github.com/coroot/coroot/issues/929",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "disclosure@vulncheck.com",
"description": [
{
"lang": "en",
"value": "CWE-601"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Coroot's unauthenticated MCP OAuth dynamic client registration endpoint accepts any syntactically valid redirect URI without validation, allowing attackers to register clients pointing to attacker-controlled hosts. Attackers can send authorization URLs to signed-in users, capture their authorization codes upon consent approval, and exchange them for access tokens to hijack MCP sessions."
}
],
"lastModified": "2026-09-23T17:17:43.030",
"sourceIdentifier": "disclosure@vulncheck.com"
}