CVE-2026-74802: SiYuan Cross-Site WebSocket Hijacking in network proxy endpoint

CVE-2026-74802 · Severity: low · CVSS 3.1 · Published 2026-10-02

SiYuan is a note-taking application whose kernel process can proxy network traffic when accessed by an authenticated admin user. An attacker who tricks an admin into visiting a malicious webpage while SiYuan is running can hijack a WebSocket connection to the proxy endpoint and direct the kernel to forward traffic to arbitrary network targets, potentially reaching internal services on the victim's network.

Technologies: github.com/siyuan-note/siyuan/kernel (Go), SiYuan Note SiYuan. Vendors: Go, SiYuan Note.

Quick answers

Is CVE-2026-74802 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-74802 being exploited in the wild.
How severe is CVE-2026-74802?
Low severity, with a CVSS score of 3.1, published 2 October 2026.
Which products and versions are affected?
github.com/siyuan-note/siyuan/kernel (Go) < 0.0.0-20260803045322-cb67e0b4fab5, SEMVER:introduced=0,fixed=0.0.0-20260803045322-cb67e0b4fab5; SiYuan Note SiYuan 3.7.3 and earlier.
Is there a fix for CVE-2026-74802?
Yes. github.com/siyuan-note/siyuan/kernel (Go): upgrade to 0.0.0-20260803045322-cb67e0b4fab5 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-74802 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-74802?
Check whether you run github.com/siyuan-note/siyuan/kernel (Go) or SiYuan Note SiYuan at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • github.com/siyuan-note/siyuan/kernel (Go): upgrade to 0.0.0-20260803045322-cb67e0b4fab5 or later
    go get github.com/siyuan-note/siyuan/kernel@v0.0.0-20260803045322-cb67e0b4fab5

Technical details

The `/ws/network/proxy` WebSocket endpoint explicitly sets `CheckOrigin: true` in its websocket.Upgrader configuration, disabling gorilla/websocket's default origin validation. Combined with the endpoint accepting fully attacker-controlled proxy targets via base64-encoded query parameters, this creates a Cross-Site WebSocket Hijacking primitive allowing an unauthenticated attacker-controlled webpage to establish a WebSocket connection and perform authenticated SSRF/network pivoting. Real-world exploitability depends on SameSite cookie configuration and requires the victim to visit the attacker's page while maintaining an active admin session.

Affected products

  • siyuan-note siyuan 3.7.3 and earlier

Identifiers

  • CVE-2026-74802
  • GHSA-3cc2-h3v6-rqpq
  • GO-2026-6650

Timeline

  • 2026-08-03: disclosed
  • 2026-10-07: advisory: GO-2026-6650 published on OSV

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.