CVE-2026-96677: Apache Juneau: Cross-site scripting via unescaped request variables in HTML-doc chrome

Published Nov 4, 2026

Updated

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Apache Juneau.

HTML document serialization does not HTML-encode variable substitutions in the page chrome (header, nav, aside, footer and similar fields). Applications whose chrome includes request-derived variables, such as request headers, form data or path values, reflect those values unencoded, allowing cross-site scripting. The default chrome does not use request variables, so only applications that add them are affected.

This issue affects Apache Juneau: through 9.2.0.

Users are recommended to upgrade to version 9.2.1, which fixes the issue.

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade Apache Juneau to a version that resolves this vulnerability.
Fixed in 9.2.1

Event History

Nov 5, 2026

CVE Published

via MITRE·11:54 AM

Data Sourced

via MITRE·11:54 AM

DescriptionWeakness

Data Sourced

via NVD·12:17 PM

DescriptionSeverityWeakness

Frequently Asked Questions

Which Apache Juneau deployments are actually exposed?

Only applications that place request-derived values in HTML document chrome are affected. Examples include request headers, form data, or path values used in header, navigation, aside, footer, or similar chrome fields; the default chrome does not use request variables.

What does an attacker need to exploit this issue?

An attacker needs a way to supply a request-derived value that the application inserts into its HTML chrome. Because those substitutions are not HTML-encoded, the supplied value can be reflected as cross-site scripting.

What should be done if the application cannot be upgraded immediately?

Remove request-derived variables from HTML document chrome fields, or ensure such values are HTML-encoded before they are used in the chrome. Upgrading to Apache Juneau 9.2.1 is the recommended fix.

How can teams determine whether their application is affected?

Review custom HTML chrome configuration and templates for substitutions sourced from request headers, form data, path values, or other request inputs. Applications using only the default chrome are not affected.

CVE-2026-96677: Apache Juneau: Cross-site scripting via unescaped request variables in HTML-doc chrome

Remediation

Event History

Frequently Asked Questions

Which Apache Juneau deployments are actually exposed?

What does an attacker need to exploit this issue?

What should be done if the application cannot be upgraded immediately?

How can teams determine whether their application is affected?

Company

Resources

Contact

Frequently Asked Questions

Which Apache Juneau deployments are actually exposed?

What does an attacker need to exploit this issue?

What should be done if the application cannot be upgraded immediately?

How can teams determine whether their application is affected?