AUGUST 4, 2026
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Case File

CVE-2026-33661

HIGH · CVSS 8.6 EPSS 0.50% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2026-03-26 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 8.6. Public exploit code or proof-of-concept references have been detected in its references.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-33661
Severity
HIGH
CVSS
8.6
EPSS
0.50%

Original NVD Description

Pay is an open-source payment SDK extension package for various Chinese payment services. Prior to version 3.7.20, the `verify_wechat_sign()` function in `src/Functions.php` unconditionally skips all signature verification when the PSR-7 request reports `localhost` as the host. An attacker can exploit this by sending a crafted HTTP request to the WeChat Pay callback endpoint with a `Host: localhost` header, bypassing the RSA signature check entirely. This allows forging fake WeChat Pay payment success notifications, potentially causing applications to mark orders as paid without actual payment. Version 3.7.20 fixes the issue.