CVSS 4.0
8.7 highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:NCVE-2026-73316
High (8.7) in xenforo xenforo. EPSS 0.3% chance of exploitation in the next 30 days.
XenForo before 2.3.13 contains a payment replay vulnerability in the PayPal REST payment provider that allows attackers to process the same webhook payload multiple times by exploiting a missing duplicate transaction ID check. Attackers can replay a valid webhook payload to trigger duplicate payment events, resulting in repeated subscription activations and unauthorized account upgrades.
Severity
CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N- EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 18% of CVEs (scores of 2026-10-31)
- CWE
- CWE-345
- Published
- Modified
- Record from
- the NVD, synced
Affected
- xenforo:xenforo
References
- https://bombobombone.github.io/posts/cve-2026-73316/
- https://github.com/BomboBombone/CVE-2026-73316
- https://www.vulncheck.com/advisories/xenforo-payment-replay-via-paypal-rest-payment-provider
- https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/
- https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/