CVE-2026-103957
Server-side request forgery in the OAuth2 discovery handling in Loom for AWS before 1.7.0 might allow an authenticated remote user to obtain the access token of another user of the deployment and to cause the application to issue requests to arbitrary internal network locations, via a crafted discovery document address supplied when registering a tool server or remote agent configured for delegated authentication.
To remediate this issue, users should upgrade to version 1.7.0 or later.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:H/VI:N/VA:N/SC:H/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: 8.2
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.38%
- Percentil entre todas las CVEs puntuadas: 30
- 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
T1550.001Application Access Tokenlateral movement80 % - Impacto secundario
T1090.001Internal Proxycommand and control75 %
UI:R requiere interacción del usuario (registrar servidor), CWE-918 es SSRF. El atacante obtiene token OAuth de otro usuario (credential theft) y fuerza requests a ubicaciones internas.
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-201, CWE-918
Referencias
JSON original (NVD)
Mostrar
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"value": "Server-side request forgery in the OAuth2 discovery handling in Loom for AWS before 1.7.0 might allow an authenticated remote user to obtain the access token of another user of the deployment and to cause the application to issue requests to arbitrary internal network locations, via a crafted discovery document address supplied when registering a tool server or remote agent configured for delegated authentication.\n\n\n\nTo remediate this issue, users should upgrade to version 1.7.0 or later."
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"lastModified": "2026-10-06T19:17:40.007",
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