Information Exposure Through Timing Discrepancy in Pay - CVE-2026-70658
Published: November 9, 2026
Vulnerability identifier: #VU162591
CSH Severity: Medium
CVSS v4: 9.1 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-70658
CWE-ID: CWE-208
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows an unauthenticated remote attacker to forge Paddle Billing webhook events and alter application billing state.
The vulnerability exists due to a non-constant-time HMAC comparison in Pay's Paddle Billing webhook signature verifier, exposing timing differences when Paddle Billing is enabled and signature guesses are submitted. An unauthenticated remote attacker can repeatedly probe /pay/webhooks/paddle_billing and measure response times to recover a valid signature, allowing forged events to pass verification and trigger billing updates.
Affected software
Pay
How to mitigate CVE-2026-70658
Install security update from vendor's website.
Pay - update to 11.6.2