RHEL 9 : containernetworking-plugins (RHSA-2026:70391)

medium Nessus Plugin ID 349147

Synopsis

The remote Red Hat host is missing one or more security updates for containernetworking-plugins.

Description

The remote Redhat Enterprise Linux 9 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2026:70391 advisory.

The Container Network Interface (CNI) project consists of a specification and libraries for writing plug- ins for configuring network interfaces in Linux containers, along with a number of supported plug-ins. CNI concerns itself only with network connectivity of containers and removing allocated resources when the container is deleted.

Security Fix(es):

* encoding/asn1: golang: Go encoding/asn1: Denial of Service via excessive recursion in Unmarshal (CVE-2026-33818)

* net/url: golang: golang net/url: Denial of Service from quadratic complexity in path resolution (CVE-2026-56860)

* net/http: golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial of Service (CVE-2026-56853)

* html/template: golang: Go html/template: Cross-Site Scripting via pathological input (CVE-2026-56858)

* crypto/tls: golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate messages (CVE-2026-56862)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL containernetworking-plugins package based on the guidance in RHSA-2026:70391.

See Also

https://access.redhat.com/errata/RHSA-2026:70391

https://access.redhat.com/security/updates/classification/#important

https://bugzilla.redhat.com/show_bug.cgi?id=2515815

https://bugzilla.redhat.com/show_bug.cgi?id=2515820

https://bugzilla.redhat.com/show_bug.cgi?id=2515827

https://bugzilla.redhat.com/show_bug.cgi?id=2515838

https://bugzilla.redhat.com/show_bug.cgi?id=2515839

http://www.nessus.org/u?5362e6b5

Plugin Details

Severity: Medium

ID: 349147

File Name: redhat-RHSA-2026-70391.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 9/23/2026

Updated: 9/23/2026

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.28

Vendor

Vendor Severity: Important

CVSS v2

Risk Factor: High

Base Score: 9.4

Temporal Score: 7

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

CVSS Score Source: CVE-2026-56858

CVSS v3

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 5.3

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

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

Vulnerability Information

CPE: cpe:/o:redhat:enterprise_linux:9, cpe:/o:redhat:rhel_eus:9.8, p-cpe:/a:redhat:enterprise_linux:containernetworking-plugins

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 9/23/2026

Vulnerability Publication Date: 8/13/2026

Reference Information

CVE: CVE-2026-33818, CVE-2026-56853, CVE-2026-56858, CVE-2026-56860, CVE-2026-56862

CWE: 1050, 770, 776, 79

RHSA: 2026:70391