CVE-2026-103858
MISP contains an incomplete authorization check in the discussion posting functionality. When a user submits a post to a thread or replies to an existing post, the application only verified whether the target thread was restricted to a single organization (org-only distribution). It did not enforce the full thread access control list, including sharing-group membership and event-level visibility.
As a result, an authenticated user who is outside the relevant sharing group or who does not have visibility on the associated event could:
- Read the thread title and the content of the quoted post
- Submit a new post into the discussion thread
Leer descripción completaMostrar menos
This constitutes both an information disclosure (reading restricted thread and post content) and an integrity issue (injecting content into a thread the user is not authorized to participate in).
Affected: <2.5.48
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/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: 5.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.22%
- Percentil entre todas las CVEs puntuadas: 11
- 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
T1210Exploitation of Remote Serviceslateral movement75 % - Impacto principal
T1005Data from Local Systemcollection80 % - Impacto secundario
T1565.001Stored Data Manipulationimpact75 %
Vulnerabilidad de autorización incompleta en MISP requiere autenticación previa (PR:L) para acceder a funcionalidad de discusión. Permite lectura no autorizada de contenido restringido (T1005) e inyección de posts sin permiso (T1565.001).
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-285
Referencias
JSON original (NVD)
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{
"id": "CVE-2026-103858",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
"ssvcData": {
"role": "Supplier",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
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}
],
"version": "2.0.3",
"timestamp": "2026-10-01T11:16:47Z"
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"timestamp": "2026-10-01T15:00:37.761849Z"
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"cvssMetricV40": [
{
"type": "Secondary",
"source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
"cvssData": {
"Safety": "NOT_DEFINED",
"version": "4.0",
"Recovery": "NOT_DEFINED",
"baseScore": 5.3,
"Automatable": "NOT_DEFINED",
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/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": "NONE",
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"attackRequirements": "NONE",
"privilegesRequired": "LOW",
"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": "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"
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},
"affected": [
{
"source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
"affectedData": [
{
"cpes": [
"cpe:2.3:a:misp:misp:*:*:*:*:*:*:*:*"
],
"repo": "https://github.com/MISP/MISP",
"vendor": "MISP",
"modules": [
"PostsController (discussion/thread posting)"
],
"product": "MISP",
"versions": [
{
"status": "affected",
"version": "unspecified",
"lessThan": "2.5.48",
"versionType": "semver"
}
],
"programFiles": [
"app/Controller/PostsController.php"
]
}
]
}
],
"published": "2026-10-01T12:17:16.080",
"references": [
{
"url": "https://github.com/MISP/MISP/commit/79fbd4c75",
"source": "5a6e4751-2f3f-4070-9419-94fb35b644e8"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "5a6e4751-2f3f-4070-9419-94fb35b644e8",
"description": [
{
"lang": "en",
"value": "CWE-285"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "MISP contains an incomplete authorization check in the discussion posting functionality. When a user submits a post to a thread or replies to an existing post, the application only verified whether the target thread was restricted to a single organization (org-only distribution). It did not enforce the full thread access control list, including sharing-group membership and event-level visibility.\n\nAs a result, an authenticated user who is outside the relevant sharing group or who does not have visibility on the associated event could:\n\n- Read the thread title and the content of the quoted post\n\n- Submit a new post into the discussion thread\n\nThis constitutes both an information disclosure (reading restricted thread and post content) and an integrity issue (injecting content into a thread the user is not authorized to participate in).\n\nAffected: <2.5.48"
}
],
"lastModified": "2026-10-01T15:17:29.540",
"sourceIdentifier": "5a6e4751-2f3f-4070-9419-94fb35b644e8"
}