Is CVE-2026-52865 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-52865 being exploited in the wild.

How severe is CVE-2026-52865?

Medium severity, with a CVSS score of 6.5, published 15 July 2026.

Which products and versions are affected?

F5 Nginx Ingress Controller 5.0.0 to 5.5.1, 2026-lts-r1 to 2026-lts-r2.

Is there a fix for CVE-2026-52865?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-52865 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-52865?

Check whether you run F5 Nginx Ingress Controller at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-52865: F5 NGINX Ingress Controller NULL pointer dereference in Ingress resources

CVE-2026-52865 · Severity: medium · CVSS 6.5 · Published 2026-07-15

F5 NGINX Ingress Controller, a tool used to manage external access to services in a Kubernetes cluster, is vulnerable to a denial-of-service attack. An authorized user with permissions to modify network resources can submit a specially crafted configuration that causes the controller to crash repeatedly. This results in a disruption of the management system (control plane), though existing network traffic (data plane) remains unaffected.

Technologies: F5 Nginx Ingress Controller. Vendors: F5.

Quick answers

Is CVE-2026-52865 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-52865 being exploited in the wild.
How severe is CVE-2026-52865?: Medium severity, with a CVSS score of 6.5, published 15 July 2026.
Which products and versions are affected?: F5 Nginx Ingress Controller 5.0.0 to 5.5.1, 2026-lts-r1 to 2026-lts-r2.
Is there a fix for CVE-2026-52865?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-52865 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-52865?: Check whether you run F5 Nginx Ingress Controller at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A NULL pointer dereference vulnerability (CWE-476) exists in the F5 NGINX Ingress Controller when processing Ingress or TransportServer resources. An authenticated remote attacker with write access to these Kubernetes resources can inject malformed data that triggers a process termination. The affected control plane process then enters a persistent crash loop as long as the malformed resource exists in the cluster. This issue affects versions 5.0.0 through 5.5.1 and 2026-lts-r1 through 2026-lts-r2; fixes are available in versions 5.5.2 and 2026-lts-r3.

Affected products

F5 NGINX Ingress Controller 5.0.0 to 5.5.1, 2026-lts-r1 to 2026-lts-r2

Timeline

2026-07-15: advisory: Original publication date

References

https://my.f5.com/manage/s/article/K000161834

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