CVE-2026-28755

Description

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.

How to fix CVE-2026-28755

To remediate CVE-2026-28755, upgrade the affected package to a fixed version below.

• —upgrade to 1.28.3-r0 or later
• —upgrade to 1.28.3 or later
• —upgrade to 1.28.3 or later
• —upgrade to 1.28.3-2 or later

Is CVE-2026-28755 being exploited?

Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.

Affected packages (4)

• from 0, < 1.28.3-r0
• >= 1.27.2, < 1.28.3, >= 1.29.0, < 1.29.7
• >= 1.27.2, < 1.28.3, >= 1.29.0, < 1.29.7
• from 0, < 1.28.3-2

CVSS scores

References (4)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2026-28755
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2026-28755
• WEBmy.f5.com/manage/s/article/K000160368
• WEBnvd.nist.gov/vuln/detail/CVE-2026-28755