Linux Distros Unpatched Vulnerability : CVE-2026-28755

medium Nessus Plugin ID 303549

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- 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.
(CVE-2026-28755)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://access.redhat.com/security/cve/cve-2026-28755

https://security-tracker.debian.org/tracker/CVE-2026-28755

Plugin Details

Severity: Medium

ID: 303549

File Name: unpatched_CVE_2026_28755.nasl

Version: 1.7

Type: Local

Agent: unix

Family: Misc.

Published: 3/25/2026

Updated: 4/1/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.3

CVSS v2

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.7

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:P/A:N

CVSS Score Source: CVE-2026-28755

CVSS v3

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 5

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Temporal Vector: CVSS:3.0/E:U/RL:U/RC:C

CVSS v4

Risk Factor: Medium

Base Score: 5.3

Threat Score: 1.3

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, p-cpe:/a:centos:centos:nginx-mod-mail, p-cpe:/a:centos:centos:nginx-mod-http-image-filter, p-cpe:/a:redhat:enterprise_linux:nginx-mod-mail, p-cpe:/a:redhat:enterprise_linux:nginx, p-cpe:/a:centos:centos:nginx-mod-devel, cpe:/o:debian:debian_linux:12.0, p-cpe:/a:centos:centos:nginx-all-modules, p-cpe:/a:redhat:enterprise_linux:nginx-mod-http-perl, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:centos:centos:nginx-mod-stream, p-cpe:/a:redhat:enterprise_linux:nginx-mod-devel, p-cpe:/a:redhat:enterprise_linux:nginx-core, cpe:/o:centos:centos:8, p-cpe:/a:centos:centos:nginx, p-cpe:/a:centos:centos:nginx-mod-http-perl, p-cpe:/a:redhat:enterprise_linux:nginx-filesystem, cpe:/o:redhat:enterprise_linux:8, cpe:/o:redhat:enterprise_linux:10, cpe:/o:debian:debian_linux:13.0, p-cpe:/a:centos:centos:nginx-mod-http-xslt-filter, p-cpe:/a:centos:centos:nginx-filesystem, p-cpe:/a:redhat:enterprise_linux:nginx-all-modules, p-cpe:/a:redhat:enterprise_linux:nginx-mod-http-image-filter, p-cpe:/a:redhat:enterprise_linux:nginx-mod-stream, p-cpe:/a:centos:centos:nginx-core, p-cpe:/a:debian:debian_linux:nginx, p-cpe:/a:redhat:enterprise_linux:nginx-mod-http-xslt-filter

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 3/24/2026

Reference Information

CVE: CVE-2026-28755