Description
XenForo before 2.3.13 contains a server-side request forgery vulnerability in the PayPal REST webhook handler that allows unauthenticated attackers to cause the server to make outbound HTTP requests to arbitrary destinations by supplying a crafted certificate URL in webhook headers without scheme, hostname, or allowlist validation. Attackers can submit a crafted POST to the PayPal webhook callback endpoint to reach internal network resources including cloud instance metadata services, potentially disclosing IAM credentials or enabling secondary internal service exploitation.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| XenForo | XenForo | < 2.3.13 | 2.3.13 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
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BomboBombone/CVE-2026-73315 ★ 0 · Sep 8, 2026
Sanitized XenForo write-up and proof of concept for CVE-2026-73315.
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
References
- Vendor Advisory vendor-advisory patch
- Release Notes release-notes
- Researcher Advisory technical-description
- Researcher PoC exploit
- https://www.vulncheck.com/advisories/xenforo-ssrf-via-paypal-rest-webhook-handler third-party-advisory