CVE-2026-73315

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.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://bombobombone.github.io/posts/cve-2026-73315/	Exploit Third Party Advisory
https://github.com/BomboBombone/CVE-2026-73315	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/xenforo-ssrf-via-paypal-rest-webhook-handler	Third Party Advisory
https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/	Release Notes
https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/	Release Notes

Configurations

Configuration 1 (hide)

cpe:2.3:a:xenforo:xenforo:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-09-08 14:17

Updated : 2026-09-11 20:31

NVD link : CVE-2026-73315

Mitre link : CVE-2026-73315

CVE.ORG link : CVE-2026-73315

JSON object : View

Products Affected

xenforo

xenforo

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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