CVE-2026-28755

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000160368	Vendor Advisory Mitigation

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:f5:nginx_plus:r33:::::::*
	cpe:2.3:a:f5:nginx_plus:r33:p1::::::
	cpe:2.3:a:f5:nginx_plus:r33:p2::::::
	cpe:2.3:a:f5:nginx_plus:r33:p3::::::
	cpe:2.3:a:f5:nginx_plus:r34:::::::*
	cpe:2.3:a:f5:nginx_plus:r34:p1::::::
	cpe:2.3:a:f5:nginx_plus:r34:p2::::::
	cpe:2.3:a:f5:nginx_plus:r35:p1::::::
	cpe:2.3:a:f5:nginx_plus:r36:::::::*
	cpe:2.3:a:f5:nginx_plus:r36:p1::::::
	cpe:2.3:a:f5:nginx_plus:r36:p2::::::

Configuration 2 (hide)

OR	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::

History

No history.

Information

Published : 2026-03-24 15:16

Updated : 2026-03-26 14:09

NVD link : CVE-2026-28755

Mitre link : CVE-2026-28755

CVE.ORG link : CVE-2026-28755

JSON object : View

Products Affected

f5

nginx_plus
nginx_open_source

CWE

CWE-863

Incorrect Authorization

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