Eclipse Vert.x up to 4.5.21/5.0.4 cross site scripting

Summaryinfo

A vulnerability has been found in Eclipse Vert.x up to 4.5.21/5.0.4 and classified as problematic. The affected element is an unknown function. The manipulation leads to cross site scripting. This vulnerability is listed as CVE-2025-11966. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Eclipse Vert.x up to 4.5.21/5.0.4 and classified as problematic. This issue affects an unknown part. The manipulation 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. The summary by CVE is:

In Eclipse Vert.x versions [4.0.0, 4.5.21] and [5.0.0, 5.0.4], when "directory listing" is enabled, file and directory names are inserted into generated HTML without proper escaping in the href, title, and link attributes. An attacker who can create or rename files or directories within a served path can craft filenames containing malicious script or HTML content, leading to stored cross-site scripting (XSS) that executes in the context of users viewing the affected directory listing.

The weakness was presented by Sho Odagiri as 303. It is possible to read the advisory at gitlab.eclipse.org. The identification of this vulnerability is CVE-2025-11966 since 10/20/2025. The exploitation is known to be difficult. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 4.5.22 or 5.0.5 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0019). Be aware that VulDB is the high quality source for vulnerability data.

Affected

• Red Hat Enterprise Linux
• Oracle Linux
• IBM InfoSphere Information Server

Productinfo

Vendor

• Eclipse

Name

• Vert.x

Version

• 4.5.0
• 4.5.1
• 4.5.2
• 4.5.3
• 4.5.4
• 4.5.5
• 4.5.6
• 4.5.7
• 4.5.8
• 4.5.9
• 4.5.10
• 4.5.11
• 4.5.12
• 4.5.13
• 4.5.14
• 4.5.15
• 4.5.16
• 4.5.17
• 4.5.18
• 4.5.19
• 4.5.20
• 4.5.21
• 5.0.0
• 5.0.1
• 5.0.2
• 5.0.3
• 5.0.4

License

• open-source

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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