CVE-2026-30834

SSRF with Full Response Exfiltration via Download Handler

A Server-Side Request Forgery (SSRF) vulnerability in the /download endpoint allows any user with API access to induce the PinchTab server to make requests to arbitrary URLs, including internal network services and local system files, and exfiltrate the full response content.

Details

The GET /download?url=<url> handler in download.go accepts a user-controlled url parameter and passes it directly to chromedp.Navigate(dlURL) without any validation or sanitization.

// internal/handlers/download.go:78
if err := chromedp.Run(ctx, chromedp.Navigate(dlURL)); err != nil {
    return fmt.Errorf("navigate to %s: %w", dlURL, err)
}

Since the request is performed by the headless Chrome browser instance managed by PinchTab, it can access:

1. Local Files: Using the file:// scheme (e.g., file:///etc/passwd).
2. Internal Services: Accessing services bound to localhost or internal network IPs that are not reachable from the outside.
3. Cloud Metadata: Accessing cloud provider metadata endpoints (e.g., 169.254.169.254).

The server then returns the captured response body directly to the attacker, enabling full exfiltration of sensitive data.

PoC

To reproduce the vulnerability, ensure the PinchTab server is running and accessible.

1. Local File Read:
   Execute the following curl command to read /etc/passwd:

   curl -X GET "http://localhost:9867/download?url=file:///etc/passwd"
   

2. Internal Service Access:
   If a service is running on localhost:8080, access it via:

   curl -X GET "http://localhost:9867/download?url=http://localhost:8080/internal-admin"
   

The response will contain the content of the targeted file or service.

PoC video:

https://github.com/user-attachments/assets/b15776ea-13cc-4534-ba7b-6d5c4e0ee74f

This is a high-severity SSRF vulnerability. It impacts the confidentiality and security of the host system and the internal network where PinchTab is deployed. Attackers can exfiltrate sensitive system files, probe internal network infrastructure, and potentially gain access to internal management interfaces or cloud credentials. While PinchTab is often used in local environments, any deployment where the API is exposed (even with authentication) allows a compromised or malicious client to pivot into the internal network.

Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside. Typical impact: access to internal metadata services, internal APIs, or cloud credentials.

CVE-2026-30834 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.7.7); upgrading removes the vulnerable code path.

Kodem intelligence

1. What is CVE-2026-30834? CVE-2026-30834 is a high-severity server-side request forgery (SSRF) vulnerability in github.com/pinchtab/pinchtab/cmd/pinchtab (go), affecting versions <= 0.7.6. It is fixed in 0.7.7. Untrusted input controls the target URL of a server-initiated request, which may reach internal services not otherwise accessible from outside.
2. How severe is CVE-2026-30834? CVE-2026-30834 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of github.com/pinchtab/pinchtab/cmd/pinchtab are affected by CVE-2026-30834? github.com/pinchtab/pinchtab/cmd/pinchtab (go) versions <= 0.7.6 is affected.
4. Is there a fix for CVE-2026-30834? Yes. CVE-2026-30834 is fixed in 0.7.7. Upgrade to this version or later.
5. Is CVE-2026-30834 exploitable, and should I be worried? Whether CVE-2026-30834 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-30834 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-30834? Upgrade github.com/pinchtab/pinchtab/cmd/pinchtab to 0.7.7 or later.