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NVD CRITICAL: CVE-2026-73056 — SiYuan kernel versions before 3.7.4 contain an improper restriction of excessive...

·Source: NIST NVD

Updated:

Executive Summary

SiYuan kernel versions before 3.7.4 contain an improper restriction of excessive authentication attempts vulnerability in the CheckAuth() middleware. The middleware accepts the API token (Conf.Api.Token) via an Authorization header (Token/Bearer) or a ?token= query parameter, and neither path is protected by the application's CAPTCHA/lockout mechanism (NeedCaptcha/WrongAuthCount). As a result, an

Analysis

SiYuan kernel versions before 3.7.4 contain an improper restriction of excessive authentication attempts vulnerability in the CheckAuth() middleware. The middleware accepts the API token (Conf.Api.Token) via an Authorization header (Token/Bearer) or a ?token= query parameter, and neither path is protected by the application's CAPTCHA/lockout mechanism (NeedCaptcha/WrongAuthCount). As a result, an unauthenticated remote attacker can perform unlimited automated guesses of the API token, particularly when a short or weak custom token has been configured, and upon success gains full RoleAdministrator access enabling arbitrary file operations and SQL queries. CVSS Score: 9.8. Published: 2026-08-16T14:16:55.083.

Indicators of Compromise (1)

CVE (1)
CVE-2026-73056
Source Attribution

Originally published by NIST NVD on Aug 16, 2026. Verified by: NIST.

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