CVE-2026-49191CWE-287

Exposed Hard-coded M3WebServer Backend API Key

Critical · published June 4, 2026

CVSS v4.0
9.3
EPSS
1%
Percentile
43.7
In the wild
Unconfirmed
What it is

The production build of the M3WebServer hard-codes its backend API keys, which can be easily intercepted through verbose error handling pages.

The record
Technical detail
CVSS v4.0
9.3 · CRITICAL
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00525 · 43.7th percentile
Weakness
CWE-287 · Improper Authentication
Published
2026-06-04T05:36Z
EPSS history
Timeline
  • 04 JUN 05:36Z
    Exposed Hard-coded M3WebServer Backend API Key
    cvelistv5