CVE-2026-58172

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.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/ThreeMammals/Ocelot/commit/f156fd4017ca25025fffdad8ec56c1d657dfb402
https://github.com/ThreeMammals/Ocelot/issues/2403
https://github.com/ThreeMammals/Ocelot/pull/2406
https://www.vulncheck.com/advisories/ocelot-ip-allow-block-list-bypass-for-websocket-upgrade-requests

Configurations

No configuration.

History

30 Jun 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-30 17:16

Updated : 2026-07-14 22:17

NVD link : CVE-2026-58172

Mitre link : CVE-2026-58172

CVE.ORG link : CVE-2026-58172

JSON object : View

Products Affected

No product.

CWE

CWE-288

Authentication Bypass Using an Alternate Path or Channel

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