Eclipse Jetty Security Constraint web.xml access control

Summaryinfo

A vulnerability was found in Eclipse Jetty and classified as critical. Affected by this issue is some unknown functionality of the file web.xml of the component Security Constraint. The manipulation results in access control. This vulnerability is cataloged as CVE-2026-18661. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in Eclipse Jetty (the affected version is unknown). Affected is an unknown code of the file web.xml of the component Security Constraint. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In Eclipse Jetty, across various versions of `jetty-annotations`, and `jetty-eeN-annotations`, the Jakarta Spec authoritative url-pattern rules for mixed `@ServletSecurity` annotation, and `web.xml` defined `security-constraint` on the same `url-pattern` were not being applied if the `web.xml` had more than 1 `url-pattern` for a servlet, and had a `security-constraint` applying to only some of those `url-pattern` definitions.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-18661 since 08/03/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/15/2026). The MITRE ATT&CK project declares the attack technique as T1068.

By approaching the search of inurl:web.xml it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-101954). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• Eclipse

Name

• Jetty

License

• free

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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