A flaw was found in Jastow. Jastow is vulnerable to Cross-Site Scripting (XSS) attack. If using a set of combined configuration to allow unescaped characters in URL with embedded Undertow and Jastow, a server might be vulnerable to improper input handling.

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:36343 advisory.

    Red Hat JBoss Enterprise Application Platform 8 is a platform for Java applications based on the WildFly     application runtime. This release of Red Hat JBoss  Enterprise Application Platform 8.1.7 serves as a     replacement for Red Hat JBoss Enterprise Application Platform 8.1.6, and includes bug fixes and     enhancements. See the Red Hat JBoss Enterprise Application Platform 8.1.7 Release Notes for information     about the most significant bug fixes and enhancements included in this release.

    Security Fix(es):

    * io.undertow.jastow-jastow: Jastow Cross-Site Scripting attack due to unsanitized URI (CVE-2025-12799)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:36342 advisory.

    Red Hat JBoss Enterprise Application Platform 8 is a platform for Java applications based on the WildFly     application runtime. This release of Red Hat JBoss  Enterprise Application Platform 8.1.7 serves as a     replacement for Red Hat JBoss Enterprise Application Platform 8.1.6, and includes bug fixes and     enhancements. See the Red Hat JBoss Enterprise Application Platform 8.1.7 Release Notes for information     about the most significant bug fixes and enhancements included in this release.

    Security Fix(es):

    * io.undertow.jastow-jastow: Jastow Cross-Site Scripting attack due to unsanitized URI (CVE-2025-12799)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page(s) listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
325528	RHEL 9 : Red Hat JBoss Enterprise Application Platform 8.1.7 (RHSA-2026:36343)	Nessus	Red Hat Local Security Checks	medium
325518	RHEL 8 : Red Hat JBoss Enterprise Application Platform 8.1.7 (RHSA-2026:36342)	Nessus	Red Hat Local Security Checks	medium

Detections

Analytics

CVE-2025-12799

medium

Tenable Plugins

medium

medium