CVE-2026-123766: Apache Axis2/Java XSS in OpenAPI module Host header

CVE-2026-123766 · Severity: info · Published 2026-11-09

Apache Axis2/Java is a web services framework that includes an OpenAPI module serving Swagger UI documentation. The module failed to encode the HTTP Host header before writing it into the Swagger UI page, allowing attackers to inject malicious JavaScript that executes in the context of the Axis2 server. This could lead to account compromise, session hijacking, or credential theft from users accessing the Swagger UI.

Technologies: Apache Axis2/Java. Vendors: Apache.

Quick answers

Is CVE-2026-123766 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-123766 being exploited in the wild.
How severe is CVE-2026-123766?
Informational severity, published 9 November 2026.
Which products and versions are affected?
Apache Axis2/Java 2.0.1.
Is there a fix for CVE-2026-123766?
Yes: fixed in 2.0.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-123766 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-123766?
Check whether you run Apache Axis2/Java 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.

How to fix

  • Fixed in: 2.0.2

Technical details

The OpenAPI module in Apache Axis2/Java 2.0.1 reflects unsanitized input from the HTTP Host header into the generated Swagger UI page, enabling stored or reflected cross-site scripting (XSS). The vulnerability requires network access to the Swagger UI endpoint and no authentication. An attacker can craft a malicious Host header to inject JavaScript executed in the browser context of the Axis2 origin.

Affected products

  • Apache Axis2/Java 2.0.1

Timeline

  • 2026-11-09: advisory

References

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