CVE Watch25 oct 2026

CVE-2026-49952

Discuz! X5.0 releases 20260320 through 20260501 contains an authentication bypass vulnerability that allows unauthenticated remote attackers

CVSS

9.1

Crítico

EPSS

4.7%

p92

KEV

—

Exploit Today

0-100

Publicado: 15 jun 2026 · Última mod.: 25 oct 2026 · CWE-323

EPSS · 30d

3.7%EPSS · 30 días4.7%

2026-10-172026-11-13

Descripción técnica

Discuz! X5.0 releases 20260320 through 20260501 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to gain unauthorized access to database backup and restore functionality by exploiting a shared cryptographic key between UCenter integration and the database backup API exposed by dbbak.php. Attackers can inject a crafted payload through the username parameter during login to abuse the encryption oracle in logging_ctl::logging_more(), obtain a legitimately signed token, and use it to bypass authorization for database export and import operations, with the additional ability to trigger a race condition to impersonate arbitrary users.

Referencias oficiales

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