siyuan versions before v3.7.4 expose the session cookie signing key through the /api/system/getConf endpoint to unauthenticated users in publish mode. Attackers can retrieve the CookieKey value and forge valid session cookies to impersonate users or gain administrative access.

Affected: Go: github.com/siyuan-note/siyuan/kernel

**CVE:** This vulnerability corresponds to [CVE-2026-72794](https://nvd.nist.gov/vuln/detail/CVE-2026-72794).

### Summary

`/api/system/getConf` returns `Conf.CookieKey`, the key used to sign the server's session cookies in its response body. The endpoint is registered with `CheckAuth` only, so the field reaches the publish `RoleReader` token and the anonymous account when `Publish.Auth.Enable` is `false`.

The configuration-export endpoint in the same file strips this exact field before returning config, so the project already treats it as secret. The reader-facing masking path does not.

### Details

| Item | Detail | |---|---| | Route | `kernel/api/router.go:70` `POST /api/system/getConf` → `model.CheckAuth` → `getConf` | | Middleware | `CheckAuth` only — no `CheckReadonly`, no `CheckAdminRole` | | Leaked field | `AppConf.CookieKey`, serialized as `cookieKey` | | Purpose of the field | Signing key for the `siyuan` session cookie |

**The field survives every stage of the masking chain.** `getConf` masks through `GetMaskedConf()` → `HideConfSecret()` (non-administrators) → `FilterConfByPublishIgnore()` (readers) → the browser-side System-path strip. `CookieKey` is removed by none of them:

- `GetMaskedConf` masks `UserData`, `MCPOAuth` and `AccessAuthCode` only. - `HideConfSecret` nulls `AI`, `Api`, `Flashcard`, `ServerAddrs`, `Publish`, `Repo`, `Sync`, `Secrets`, `Variables` and the System paths. It contains no reference to `CookieKey`. - `FilterConfByPublishIgnore` touc…