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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact High

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
XenForo XenForo unaffected
Version Status Constraints
0 affected < 2.3.13

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Project Subscriptions

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://www.vulncheck.com/advisories/xenforo-ssrf-via-paypal-rest-webhook-handler cve-icon
https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/ cve-icon
https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/ cve-icon
History

Tue, 08 Sep 2026 13:30:00 +0000

Type Values Removed Values Added
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.
Title XenForo < 2.3.13 SSRF via PayPal REST Webhook Handler
Weaknesses CWE-918
References
Metrics cvssV3_1

{'score': 8.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N'}

cvssV4_0

{'score': 7.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-08T13:42:29.920Z

Reserved: 2026-08-11T19:56:20.007Z

Link: CVE-2026-73315

cve-icon Vulnrichment

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cve-icon NVD

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cve-icon Redhat

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cve-icon OpenCVE Enrichment

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Weaknesses