SiYuan before v3.7.4 Publish-Boundary Bypass via WebSocket

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No exploitation or prediction data is available here for these CVEs. This does not mean they are safe or unlikely to be exploited.

SiYuan versions before v3.7.4 contain a publish-boundary bypass vulnerability in WebSocket broadcast sessions that allows anonymous readers to receive unfiltered edits. Attackers can establish a WebSocket connection to the publish surface and passively receive real-time content events including password-protected and forbidden documents without authentication.

Source published

14 Aug 2026 11:35:24 UTC

Source modified

18 Aug 2026 02:26:57 UTC

Saved here

23 Oct 2026 15:48:27 UTC

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CVE Program Terms of Use

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CVSS 4.0 · 9.2 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

CVSS 3.1 · 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

SiYuan versions before v3.7.4 contain a publish-boundary bypass vulnerability in WebSocket broadcast sessions that allows anonymous readers to receive unfiltered edits. Attackers can establish a WebSocket connection to the publish surface and passively receive real-time content events including password-protected and forbidden documents without authentication.

Source published

Aug 14, 2026, 11:35:24 AM (timezone not stated)

Source modified

Aug 18, 2026, 2:26:57 AM (timezone not stated)

Saved here

13 Nov 2026 17:03:47 UTC

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ENISA EUVD · source terms and attribution apply

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EUVD CVSS 4.0 · 9.2 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

SiYuan versions before v3.7.4 contain a publish-boundary bypass vulnerability in WebSocket broadcast sessions that allows anonymous readers to receive unfiltered edits. Attackers can establish a WebSocket connection to the publish surface and passively receive real-time content events including password-protected and forbidden documents without authentication.

Source published

14 Aug 2026 12:16:43 UTC

Source modified

26 Aug 2026 17:04:11 UTC

Saved here

25 Oct 2026 15:19:03 UTC

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NIST NVD usage terms; underlying source attribution retained

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Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 4.0 · [email protected] · Secondary · 9.2 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/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

CVSS 3.1 · [email protected] · Secondary · 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

**CVE:** This vulnerability corresponds to [CVE-2026-72810](https://nvd.nist.gov/vuln/detail/CVE-2026-72810). ### Summary WebSocket sessions established through the publish surface (port 6808, `RoleReader` anonymous when `Publish.Auth.Enable` is `false`) are added to the same broadcast session pool as authenticated sessions. The kernel's broadcast functions push content events transactions carrying block DOM, document save/create, move/rename to every session in the pool with no role or publish-access filtering. As a result, an anonymous reader who holds a WebSocket connection open passively receives a real-time feed of every edit made in the workspace, including edits to password-protected, publish-forbidden, and unpublished documents. Because these events are delivered over the push channel and never pass through an HTTP handler, none of the publish-access filters that gate the HTTP endpoints apply. ### Details **Session admission.** `HandleConnect` admits the injected `RoleReader` publish token, and the session is registered via `AddPushChan` into the same `sessions` pool used for authenticated clients. **Unfiltered broadcast.** The broadcast functions (`Broadcast`, `broadcastOthers`, `broadcastOtherAppMains`, …) write to every session in the pool with no role or publish-access check. The `isPublish` flag on a session is consulted only to send the "service closed" notice it is never used to gate content. Content events are pushed via `PushModeBroadcast → Broadcast()`, so transactions (with rendered block DOM), `savedoc`/create, and `moveDoc`/rename events reach the publish reader's socket unfiltered. **No HTTP filter applies.** This is a push channel, the events originate from the kernel's own edit pipeline and are broadcast directly to open sockets. They never traverse an HTTP handler, so the publish-access filters that gate the HTTP content endpoints (and the incomplete/missing filters reported separately on those endpoints) are not in the path at all. The WebSocket route (`/ws`) is `CheckAuth`-only, which the publish `RoleReader` token satisfies. ### Proof of Concept Reproduced on a local instance (SiYuan running locally, publish mode enabled on port 6808, publish Basic Auth disabled). An anonymous client (no token, no password) opens `wss://127.0.0.1:6808/ws` and holds it open while an administrator edits documents in the workspace. The anonymous socket received, in real time and unfiltered: - `updateAttrs` with `name=WS_LEAK_SECRET_9931` on a block whose `rootID` is a **password-protected** document. - The secret title `WS_SECRET_DOC_7742` of a newly created document. - The create event carrying the notebook (box) name `CritChain` and the document path. No HTTP request was made beyond the WebSocket upgrade; the content arrived over the push channel. ### Impact An anonymous reader (publish mode with auth disabled) or any publish `RoleReader` who merely holds a WebSocket connection open receives a live feed of every edit an administrator makes: block DOM, attributes, titles, notebook names, and document structure, including for password-protected, publish-forbidden, and unpublished documents. This defeats the publish-access and publish-password boundaries entirely for any content edited while the socket is open. The precondition is trivial: an administrator active in the workspace while the anonymous socket is connected. Confidentiality-only (passive disclosure); the channel is receive-only for the reader. Encrypted-notebook content follows the same broadcast path if edited while unlocked. ### Suggested fix Filter broadcasts by session before writing: for any session flagged `isPublish`, apply the same publish-access/publish-ignore/publish-password checks used on the HTTP content path before pushing a content event, or exclude publish sessions from content broadcasts entirely and deliver only the events a publish viewer is authorized to see. The `isPublish` flag is already present on the session; it should gate content, not only the service-closed notice.

Source published

3 Sep 2026 22:30:52 UTC

Source modified

10 Sep 2026 15:25:58 UTC

Saved here

24 Oct 2026 13:19:41 UTC

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GitHub Advisory Database · CC-BY-4.0

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Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Publisher rating · HIGH

## Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-mw8r-mw84-88v2. This link is maintained to preserve external references. ## Original Description SiYuan versions before v3.7.4 contain a publish-boundary bypass vulnerability in WebSocket broadcast sessions that allows anonymous readers to receive unfiltered edits. Attackers can establish a WebSocket connection to the publish surface and passively receive real-time content events including password-protected and forbidden documents without authentication.

Source published

14 Aug 2026 12:31:24 UTC

Source modified

3 Sep 2026 22:45:04 UTC

Saved here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/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

Publisher rating · CRITICAL

SiYuan: Publish-boundary bypass via WebSocket broadcast: anonymous readers receive a live unfiltered feed of all edits including protected/forbidden documents (publish mode) in github.com/siyuan-note/siyuan/kernel

Source published

10 Sep 2026 14:48:42 UTC

Source modified

10 Sep 2026 15:15:13 UTC

Saved here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

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