CVE-2026-73316 (GCVE-0-2026-73316)
Vulnerability from cvelistv5 – Published: 2026-09-08 13:18 – Updated: 2026-10-01 15:20
VLAI
EPSS
VEX
Title
XenForo < 2.3.13 Payment Replay via PayPal REST Payment Provider
Summary
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
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 13:50 UTC
CWE
- CWE-345 - Insufficient Verification of Data Authenticity
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://xenforo.com/community/threads/security-fi… | vendor-advisorypatch |
| https://xenforo.com/community/threads/xenforo-2-3… | release-notes |
| https://bombobombone.github.io/posts/cve-2026-73316/ | technical-description |
| https://github.com/BomboBombone/CVE-2026-73316 | exploit |
| https://www.vulncheck.com/advisories/xenforo-paym… | third-party-advisory |
Impacted products
Date Public
2026-09-07 00:00
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