8.7

CVE-2026-73054: siyuan-note siyuan Improper Authentication

CVSS: 8.7v4.0HighDeferred
Published 15-08-2026Last modified 17-08-2026

Vulnerability summary

CVE-2026-73054 is a high (CVSS 8.7) Improper Authentication vulnerability in siyuan-note siyuan. EPSS estimates a 0.54% chance of exploitation in the next 30 days, higher than 44.5% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.7/10
010
High · v4.0 (CVE.org)
EPSS score
0.54%
0%100%
Low · +0.23 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 versions before v3.7.4 contain an authentication bypass vulnerability in the WebSocket endpoint caused by differential parsing of query parameters between authentication exemption and session quarantine checks. Unauthenticated attackers can craft a malicious WebSocket URI with duplicated query parameters to bypass access auth code validation and receive the live kernel event stream including document identifiers, titles, and operation logs.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.54%

Chance of exploitation in the next 30 days

Percentile

45%

Versus all other CVEs

30-day change

+0.23 pp

From 0.31% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.54%

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