NGINX ngx_stream_ssl_module Revoked Cert Bypass via OCSP
CVE-2026-28755 Published on March 24, 2026

NGINX ngx_stream_ssl_module vulnerability
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_stream_ssl_module module due to the improper handling of revoked certificates when configured with the ssl_verify_client on and ssl_ocsp on directives, allowing the TLS handshake to succeed even after an OCSP check identifies the certificate as revoked.   Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-28755 can be exploited with network access, and requires small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a small impact on confidentiality and integrity, and no impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
LOW
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
LOW
Integrity Impact:
LOW
Availability Impact:
NONE

Weakness Type

What is an AuthZ Vulnerability?

The software performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

CVE-2026-28755 has been classified to as an AuthZ vulnerability or weakness.


Products Associated with CVE-2026-28755

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F5 Networks Nginx Open Source
 
F5 Networks Nginx Plus
 

Affected Versions

F5 NGINX Open Source: F5 NGINX Plus: