CyberSecBulletin
CVE-2026-66786NVD status: Awaiting Analysis

Red Hat Advanced Cluster Management for…: Improper Control of Generation of Code

CVE-2026-66786 is a critical-severity improper control of generation of code vulnerability in Red Hat Advanced Cluster Management for Kubernetes 2.16 from Red Hat, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 1.37% chance of exploitation within 30 days, higher than 72% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Red Hat Advanced Cluster Management for Kubernetes 2.16 you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
Red HatRed Hat Advanced Cluster Management for Kubernetes 2.16Not specified in the recordNot stated
Red HatRed Hat Advanced Cluster Management for Kubernetes 2.17Not specified in the recordNot stated
Red HatRed Hat Advanced Cluster Management for Kubernetes 2Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (redhat.com).

Official description

A flaw was found in submariner. In cert-auth mode, the connection configuration is built using free-form strings from the Custom Resource Definition (CRD) without proper validation. A malicious cluster can exploit this by publishing a CableName that includes newlines and ipsec.conf directives. This allows an attacker to inject arbitrary configuration parameters or execute commands through leftupdown hooks, leading to remote code execution as root on the gateway node.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

How developers prevent this class of flaw

  • Refactor your program so that you do not have to dynamically generate code.
  • Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
  • Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

More Improper Control of Generation of Code vulnerabilities (CWE-94)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Red Hat Advanced Cluster Management for Kubernetes 2.16

All Red Hat Advanced Cluster Management for Kubernetes 2.16 vulnerabilities

Recent Improper Control of Generation of Code vulnerabilities

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