9.8

CVE-2026-73046: siyuan-note siyuan

CVSS: 9.8v3.1CriticalDeferred
Published 15-08-2026Last modified 17-08-2026

Vulnerability summary

CVE-2026-73046 is a critical (CVSS 9.8) vulnerability in siyuan-note siyuan. EPSS estimates a 0.79% chance of exploitation in the next 30 days, higher than 55.5% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.79%
0%100%
Low · +0.37 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 15-08-2026
    PublishedVulnerability first disclosed.
  2. 17-08-2026
    Last modifiedVulnerability information updated.

Description

SiYuan before v3.7.4 improperly restricts excessive authentication attempts in the CheckAuth() middleware. The HTTP Basic Authentication branch, which guards nearly the entire /api/* surface, accepts the workspace access code (Conf.AccessAuthCode) as the Basic Auth password but never consults the CAPTCHA/lockout gate or increments the failure counter used by the cookie/session login path. This allows unauthenticated remote attackers to brute-force the admin access code with unlimited automated requests and obtain full RoleAdministrator access to the kernel. A secondary weakness exists because the access code is compared using a non-constant-time string comparison.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.79%

Chance of exploitation in the next 30 days

Percentile

56%

Versus all other CVEs

30-day change

+0.37 pp

From 0.43% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.79%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Siyuan-note1 product

1 vendor · 1 product

References

2 links