CVE-2026-59640

Estado: AnalizadaAlta (8.7)—

In Bouncy Castle for Java before 1.85, OpenPGP CFB quick-check oracle active on symmetric/session-key paths. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpg-fips 1.0.13 (1.0.X series), 2.0.13 (2.0.X series) and 2.1.13 (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:N/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: 8.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.35%
Percentil entre todas las CVEs puntuadas: 26
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 access75 %
Impacto principalT1040 Network Sniffingcredential access · discovery65 %
Impacto secundarioT1557 Adversary-in-the-Middlecredential access · collection60 %

Aplicación de cifrado OpenPGP expuesta en red remota sin autenticación (AV:N PR:N) susceptible a ataque de oráculo criptográfico (CWE-203) que filtra información de clave de sesión, permitiendo recuperación parcial de datos cifrados (VC:H).

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 Encrypt Sensitive Information Vulnerability Scanning User Training

Tecnologías afectadas (3)

Bouncycastle — Bc-java Bouncycastle — Bcpg-fips Bouncycastle — Bouncy Castle FOR Java LTS

CWE

CWE-203

Referencias

JSON original (NVD)

Mostrar

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