SiYuan: Cross-Site WebSocket Hijacking on the admin-only network proxy endpoint (/ws/network/proxy) via explicit CheckOrigin: true bypass

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

not scored

EPSS

• CVE-2026-74802: 0.16% estimated exploitation activity in the next 30 days; percentile 5.60 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

High Package gomod github.com/siyuan-note/siyuan/kernel Affected versions 3.7.3 Patched versions (none yet — leave blank until a fix is released) Description Summary /ws/network/proxy is an admin-only WebSocket forward-proxy endpoint (target URL and headers fully attacker-specifiable via query parameters). Its websocket.Upgrader explicitly overrides CheckOrigin to unconditionally return true — disabling the origin validation that the gorilla/websocket library otherwise enforces by default. WebSocket handshake requests are not subject to CORS preflight at all (unlike fetch/XHR), so origin validation for WebSocket endpoints has to be done deliberately by the server; here it has been deliberately turned off instead. Combined with the endpoint's own query-parameter-driven proxy target, this is a textbook Cross-Site WebSocket Hijacking (CSWSH) primitive on a capability that amounts to an authenticated network pivot through the SiYuan kernel process. Details Route registration…

Published by the source

2 Oct 2026, 22:46 UTC

Last modified by the source

7 Oct 2026, 17:45 UTC

Source last checked

26 Oct 2026, 15:29 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-3cc2-h3v6-rqpq

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6650

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-3cc2-h3v6-rqpq

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# Patch Next advisory brief: CVE-2026-74802

Advisory: SiYuan: Cross-Site WebSocket Hijacking on the admin-only network proxy endpoint (`/ws/network/proxy`) via explicit `CheckOrigin: true` bypass
IDs: CVE-2026-74802, GHSA-3cc2-h3v6-rqpq
Record: https://patchnext.com/advisories/cve-2026-74802 (revision 3, source checked 26 Oct 2026, 15:29 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Unrated
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/siyuan-note/siyuan/kernel 0.0.0-20260803045322-cb67e0b4fab5. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/siyuan-note/siyuan/kernel: affected < 0.0.0-20260803045322-cb67e0b4fab5; fixed in 0.0.0-20260803045322-cb67e0b4fab5

## Suggested inspection (read-only)
- Go github.com/siyuan-note/siyuan/kernel: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/siyuan-note/siyuan/kernel.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6650 (OSV record GO-2026-6650 lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260803045322-cb67e0b4fab5 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-3cc2-h3v6-rqpq (OSV record GHSA-3cc2-h3v6-rqpq lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260803045322-cb67e0b4fab5 (fixed))
- Verified: https://github.com/advisories/GHSA-3cc2-h3v6-rqpq (GitHub-reviewed advisory GHSA-3cc2-h3v6-rqpq lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260803045322-cb67e0b4fab5)

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