CVE-2026-55241
Checkmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations. Prior to 3.9.1, the public POST /api/v1/auth/register route in server/src/api/routes/authRoutes.ts passes multipart profileImage uploads through in-memory Multer parsing before registration validation, without file-size, file-count, or MIME-type limits in server/src/api/middleware/upload.ts. An unauthenticated attacker can submit concurrent oversized files that are buffered before invalid registration or invite-token checks reject the request, exhausting memory and crashing or destabilizing the backend. This issue is fixed in version 3.9.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.62%
- Percentil entre todas las CVEs puntuadas: 48
- 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
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1499.004Application or System Exploitationimpact90 %
POST /api/v1/auth/register expuesto sin autenticación en red (AV:N, PR:N, UI:N). Ausencia de límites en tamaño de archivo causa agotamiento de memoria y DoS de aplicación.
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-400, CWE-770
Referencias
- https://github.com/bluewave-labs/Checkmate/commit/091c36cbf338b673110b0806d76df26d52516468
- https://github.com/bluewave-labs/Checkmate/releases/tag/v3.9.1
- https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-9xvg-x28f-m78m
- https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-9xvg-x28f-m78m
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-55241",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-55241",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "poc"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-08-25T11:47:48.710908Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security-advisories@github.com",
"affectedData": [
{
"vendor": "bluewave-labs",
"product": "Checkmate",
"versions": [
{
"status": "affected",
"version": "< 3.9.1"
}
]
}
]
}
],
"published": "2026-08-21T18:16:48.790",
"references": [
{
"url": "https://github.com/bluewave-labs/Checkmate/commit/091c36cbf338b673110b0806d76df26d52516468",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/bluewave-labs/Checkmate/releases/tag/v3.9.1",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-9xvg-x28f-m78m",
"source": "security-advisories@github.com"
},
{
"url": "https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-9xvg-x28f-m78m",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "security-advisories@github.com",
"description": [
{
"lang": "en",
"value": "CWE-400"
},
{
"lang": "en",
"value": "CWE-770"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Checkmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations. Prior to 3.9.1, the public POST /api/v1/auth/register route in server/src/api/routes/authRoutes.ts passes multipart profileImage uploads through in-memory Multer parsing before registration validation, without file-size, file-count, or MIME-type limits in server/src/api/middleware/upload.ts. An unauthenticated attacker can submit concurrent oversized files that are buffered before invalid registration or invite-token checks reject the request, exhausting memory and crashing or destabilizing the backend. This issue is fixed in version 3.9.1."
}
],
"lastModified": "2026-09-18T20:09:01.757",
"sourceIdentifier": "security-advisories@github.com"
}