F5 NGINX Ingress Controller up to 5.5.1 Control Plane infinite loop

Summaryinfo

A vulnerability classified as problematic has been found in F5 NGINX Ingress Controller up to 5.5.1. This issue affects some unknown processing of the component Control Plane. This manipulation causes infinite loop. This vulnerability appears as CVE-2026-52865. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability has been found in F5 NGINX Ingress Controller up to 5.5.1 and classified as problematic. Affected by this vulnerability is some unknown processing of the component Control Plane. The manipulation with an unknown input leads to a infinite loop vulnerability. The CWE definition for the vulnerability is CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. As an impact it is known to affect availability. The summary by CVE is:

When NGINX Ingress Controller processes Ingress or TransportServer resources, an authenticated, remote attacker with permission to create or modify Ingress or TransportServer resources can cause the NGINX Ingress Controller process to terminate. Impact: The NGINX Ingress Controller control plane process terminates and enters a persistent crash loop while the malformed Ingress or TransportServer resource remains in the cluster. This vulnerability allows a remote, authenticated attacker with at least Ingress or TransportServer resource write access to cause a denial-of-service (DoS) on the NGINX Ingress Controller system. There is no data plane exposure; this is a control plane issue only. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

The advisory is shared at my.f5.com. This vulnerability is known as CVE-2026-52865 since 06/18/2026. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are necessary for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 5.5.2 or 2026-lts-r3 eliminates this vulnerability.

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Productinfo

Type

• Web Server

Vendor

• F5

Name

• NGINX Ingress Controller

Version

• 5.5.0
• 5.5.1

License

• commercial

Website

• Vendor: https://f5.com/

CPE 2.3info

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CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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