What’s Vulnerable › Vulnerabilities

CVE-2026-74802: SiYuan 3.7.3 Cross-Site WebSocket Hijacking via network proxy

• Severity: high (CVSS 8.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-17 · updated 2026-08-28
• Weakness: CWE-346

Description

SiYuan versions before 3.7.4 contain a cross-site WebSocket hijacking vulnerability in the admin-only /ws/network/proxy endpoint that explicitly disables origin validation by setting CheckOrigin to unconditionally return true. Attackers can craft malicious webpages that establish WebSocket connections to this endpoint and direct the SiYuan kernel process to proxy arbitrary network traffic to attacker-chosen targets, enabling authenticated network pivoting through the victim's machine.

Affected products

• siyuan-note siyuan: before 3.7.4 — fixed in 3.7.4

How to fix

Upgrade to a fixed version: siyuan-note siyuan 3.7.4. Check the vendor advisory for mitigations.

References

• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3cc2-h3v6-rqpq
• https://www.vulncheck.com/advisories/siyuan-cross-site-websocket-hijacking-via-network-proxy
• https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3cc2-h3v6-rqpq

Get alerted when CVE-2026-74802 or the next vulnerability affects your stack