CVE-2026-8763

Estado: AnalizadaCrítica (9.3)—

In Bouncy Castle for Java before 1.85, Name Constraints bypass via trailing dot in rfc822Name and URI. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).

CVSS

Versión: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/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:Amber
Puntuación base: 9.3

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.43%
Percentil entre todas las CVEs puntuadas: 35
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access85 %
Impacto principalT1557 Adversary-in-the-Middlecredential access · collection80 %
Impacto secundarioT1212 Exploitation for Credential Accesscredential access75 %

Vulnerabilidad de elusión de Name Constraints en certificados (CWE-295) accesible remotamente sin autenticación (AV:N/PR:N/UI:N). Permite falsificar certificados de dominios confiables, facilitando ataques MITM y compromiso de credenciales en comunicaciones cifradas.

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

Network Segmentation Limit Access to Resource Over Network Filter Network Traffic Application Isolation and Sandboxing Exploit Protection Update Software

Tecnologías afectadas (3)

Bouncycastle — Bc-java Bouncycastle — Bouncy Castle FOR Java LTS Bouncycastle — Fips Java API

CWE

CWE-295

Referencias

JSON original (NVD)

Mostrar

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