Is CVE-2026-101581 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-101581 being exploited in the wild.

How severe is CVE-2026-101581?

Medium severity, with a CVSS score of 6.5, published 20 October 2026.

Which products and versions are affected?

Oracle Helidon 4.0.0-4.5.5, 27.0.0.

Is there a fix for CVE-2026-101581?

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-2026-101581 attacked?

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

Am I affected by CVE-2026-101581?

Check whether you run Oracle Helidon 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-2026-101581: Oracle Helidon DNS resolver spoofing in web client

CVE-2026-101581 · Severity: medium · CVSS 6.5 · Published 2026-10-20

Helidon is a lightweight framework used to build Java-based microservices and web applications. An attacker with network access can spoof DNS responses to hijack connections made by Helidon applications, leading to data tampering and service disruption without requiring authentication. This could allow an attacker to modify or delete application data and cause temporary outages.

Technologies: Oracle Helidon. Vendors: Oracle.

Quick answers

Is CVE-2026-101581 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-101581 being exploited in the wild.
How severe is CVE-2026-101581?: Medium severity, with a CVSS score of 6.5, published 20 October 2026.
Which products and versions are affected?: Oracle Helidon 4.0.0-4.5.5, 27.0.0.
Is there a fix for CVE-2026-101581?: 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-2026-101581 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-101581?: Check whether you run Oracle Helidon 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

An unauthenticated attacker with network access can exploit a vulnerability in the helidon-webclient-dns-resolver-round-robin component to conduct DNS spoofing attacks. The vulnerability allows integrity compromise and partial denial of service on affected versions through network-based DNS manipulation. The issue affects Helidon 4.0.0 through 4.5.5 and version 27.0.0.

Affected products

Oracle Helidon 4.0.0-4.5.5, 27.0.0

Timeline

2026-10-20: disclosed

References

https://www.oracle.com/security-alerts/cpuoct2026.html

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