CVE-2026-73054: siyuan-note siyuan Improper Authentication
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.
Timeline
- 15-08-2026PublishedVulnerability first disclosed.
- 17-08-2026Last 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- NVDNIST8.7HighCVSS: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:X
- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Siyuan-note1 product
- siyuan< 3.7.4
1 vendor · 1 product
References
2 links- www.vulncheck.com/advisories/siyuan-before-authentication-bypass-via-websocketThird Party Advisory