CVE-2026-58172CWE-288

Ocelot - IP Allow/Block List Bypass for WebSocket Upgrade Requests

Critical · published June 30, 2026

CVSS v4.0
9.3
EPSS
1%
Percentile
46.2
In the wild
Unconfirmed
What it is

Ocelot through 24.1.0, fixed in commit f156fd4, contains a security control bypass vulnerability that allows denied clients to circumvent IP-based access restrictions by sending WebSocket upgrade requests. The WebSocket upgrade pipeline branch configured via MapWhen in OcelotPipelineExtensions.cs omits SecurityMiddleware, causing requests from blocked IP addresses to be proxied to downstream services without enforcement of the configured allow/block list.

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:N/SC:N/SI:N/SA:N
EPSS
0.00565 · 46.2th percentile
Weakness
CWE-288 · Authentication Bypass Using an Alternate Path or Channel
Published
2026-06-30T15:54Z
EPSS history
Timeline
  • 30 JUN 15:54Z
    Ocelot - IP Allow/Block List Bypass for WebSocket Upgrade Requests
    cvelistv5