CVE-2026-48051

Papra HTTP redirect bypass can lead to SSRF via webhook delivery system

• Any authenticated org member (no admin role required) can trigger the exploit.
• The Papra server makes HTTP requests to internal addresses blocked by its own SSRF list: 127.0.0.0/8, 169.254.0.0/16, RFC-1918 ranges.
• This is blind SSRF, internal response bodies are written to webhook_deliveries but no API route exposes delivery records. Response content is not accessible to the attacker through the Papra API.
• Internal network topology can be partially inferred from whether requests succeed or fail (closed port produces a network error; open port returns an HTTP response).
• HTTP 307 redirects preserve the POST method and body, enabling state-changing requests to internal services that accept unauthenticated POSTs.
• On cloud deployments (AWS, GCP, Azure), the instance metadata service at 169.254.169.254 is reachable by the same technique. Cloud IMDS was not tested in this PoC (local Docker environment, no metadata service present). Response exfiltration via the Papra API remains unavailable regardless.

Suggested Fix

Add redirect: 'manual' to the ofetch.raw() call in packages/webhooks/src/webhooks.services.ts (line 16) and treat any 3xx response as a delivery failure. Webhook endpoints have no legitimate reason to redirect:

const response = await ofetch.raw<unknown>(url, {
  ...options,
  redirect: 'manual',       // do not follow redirects
  ignoreResponseError: true,
});

If redirect-following is ever required in the future, validate the Location header through the existing isUrlSsrfSafe() check before re-issuing the request.

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-2026-48051 has a CVSS score of 3.5 (Low). The vector is network-reachable, low 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 (0.3.3); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

1. What is CVE-2026-48051? CVE-2026-48051 is a low-severity server-side request forgery (SSRF) vulnerability in @papra/webhooks (npm), affecting versions < 0.3.3. It is fixed in 0.3.3. 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-2026-48051? CVE-2026-48051 has a CVSS score of 3.5 (Low). 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 @papra/webhooks are affected by CVE-2026-48051? @papra/webhooks (npm) versions < 0.3.3 is affected.
4. Is there a fix for CVE-2026-48051? Yes. CVE-2026-48051 is fixed in 0.3.3. Upgrade to this version or later.
5. Is CVE-2026-48051 exploitable, and should I be worried? Whether CVE-2026-48051 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-2026-48051 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-2026-48051? Upgrade @papra/webhooks to 0.3.3 or later.