8.7
CVE-2026-73314
- EPSS 0.45%
- Veröffentlicht 08.09.2026 13:17:52
- Zuletzt bearbeitet 11.09.2026 20:31:16
- Erkennungen
XenForo < 2.3.13 Signature Verification Bypass via PayPal REST Webhook
XenForo before 2.3.13 contains a signature verification logic error in the PayPal REST webhook handler that allows unauthenticated attackers to bypass payment signature validation by submitting a webhook request with an unsupported auth_algo header value. When the algorithm cannot be mapped to a supported hash function, the verification function incorrectly returns true instead of failing, causing the caller to treat the fabricated request as verified and process the payment event without a valid PayPal signature.
| Typ | Quelle | Score | Percentile |
|---|---|---|---|
| EPSS | FIRST.org | 0.45% | 0.379 |
| Quelle | Base Score | Exploit Score | Impact Score | Vector String |
|---|---|---|---|---|
| disclosure@vulncheck.com | 8.7 | 0 | 0 |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
|
| disclosure@vulncheck.com | 7.5 | 3.9 | 3.6 |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
|
CWE-754 Improper Check for Unusual or Exceptional Conditions
The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product.
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/
https://www.vulncheck.com/advisories/xenforo-signature-verification-bypass-via-paypal-rest-webhook
https://bombobombone.github.io/posts/cve-2026-73314/
https://github.com/BomboBombone/CVE-2026-73314