Eclipse Mojarra up to 4.0.28/4.1.19/5.0.0-M11 Client Window jfwid/jakarta.faces.ClientWindow cross site scripting

Summaryinfo

A vulnerability was found in Eclipse Mojarra up to 4.0.28/4.1.19/5.0.0-M11. It has been declared as problematic. The impacted element is an unknown function of the component Client Window. Such manipulation of the argument jfwid/jakarta.faces.ClientWindow leads to cross site scripting. This vulnerability is listed as CVE-2026-120421. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Eclipse Mojarra up to 4.0.28/4.1.19/5.0.0-M11. It has been rated as problematic. Affected by this issue is some unknown processing of the component Client Window. The manipulation of the argument jfwid/jakarta.faces.ClientWindow with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

In Eclipse Mojarra versions 2.2.0 through 4.0.28, 4.1.0 through 4.1.19, and 5.0.0-M1 through 5.0.0-M11, when URL client window mode is enabled (`jakarta.faces.CLIENT_WINDOW_MODE=url`), the client window id from the `jfwid` or `jakarta.faces.ClientWindow` request parameter is appended to generated URLs without URL-encoding. `h:button` renders such a URL into a JavaScript string literal, which allows reflected cross-site scripting. With `com.sun.faces.enableCspNonce=true`, the injected script runs on page load inside the nonce script element, bypassing the Content Security Policy.

The advisory is shared for download at gitlab.eclipse.org. This vulnerability is handled as CVE-2026-120421 since 11/02/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 4.0.29, 4.1.20 or 5.0.0-M12 eliminates this vulnerability.

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Productinfo

Vendor

• Eclipse

Name

• Mojarra

Version

• 4.0.0
• 4.0.1
• 4.0.2
• 4.0.3
• 4.0.4
• 4.0.5
• 4.0.6
• 4.0.7
• 4.0.8
• 4.0.9
• 4.0.10
• 4.0.11
• 4.0.12
• 4.0.13
• 4.0.14
• 4.0.15
• 4.0.16
• 4.0.17
• 4.0.18
• 4.0.19
• 4.0.20
• 4.0.21
• 4.0.22
• 4.0.23
• 4.0.24
• 4.0.25
• 4.0.26
• 4.0.27
• 4.0.28
• 4.1.0
• 4.1.1
• 4.1.2
• 4.1.3
• 4.1.4
• 4.1.5
• 4.1.6
• 4.1.7
• 4.1.8
• 4.1.9
• 4.1.10
• 4.1.11
• 4.1.12
• 4.1.13
• 4.1.14
• 4.1.15
• 4.1.16
• 4.1.17
• 4.1.18
• 4.1.19
• 5.0.0-M11

License

• open-source

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CPE 2.2info

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