CVE-2026-73316

highpriority · track · 40OT risk · elevatedEPSS 0.003 · 18 %ileexploit · PoCUS
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
1 exploit · PoC
Likely / severe?
0.27% (18th) EPSS
CVSS 7.5 · high
Is it mine?
1 products
Check your exposure
Who says so?
1 sources
nvd

EPSS · scored 2026-10-28

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.7
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · disclosure@vulncheck.comexploitability 3.9 · impact 3.6
v4.08.7highCVSS: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:Xsecondary · disclosure@vulncheck.com
v4.07.7highCVSS: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:P/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:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

exploits (1)

Public proof-of-concept and weaponised exploit code.

05

affected products (1)

Products and version ranges known to be affected.

06

sources

Which sources assert this record, and when.

published 2026-09-08modified 2026-09-11
07

references (5) nvd

External citations — patches, advisories, analysis.

scry

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