CVE-2026-18662 Eclipse Foundation CVE debrief

Who should care

Defenders and administrators responsible for configuring and maintaining Eclipse Jetty deployments should assess their configurations to ensure proper security constraint combination and verify the applicability of this vulnerability to their specific deployments.

Why it matters

CVE-2026-18662 is a medium-severity vulnerability affecting Eclipse Jetty, specifically in the `jetty-security` and `jetty-eeN-security` components across various versions. The issue arises from the improper combination of two or more security constraints with the same http-method-omission set and no url-patterns, as per the Jakarta Servlet Specification. This could lead to later http-method-omission sets overriding previous constraints with the same http-method-omission set. Defenders should prioritize reviewing and updating their Jetty configurations to ensure proper constraint combination and verify the applicability of this vulnerability to their specific deployments.

• Defenders need to verify if their Jetty deployments are affected by this vulnerability and assess the potential impact on their security configurations.
• Proper security constraint combination is crucial to prevent unintended access or privilege escalation in Jetty deployments.
• Defenders should prioritize reviewing and updating their Jetty configurations to ensure proper constraint combination and verify the applicability of this vulnerability to their specific deployments.

Technical summary

The vulnerability arises from the improper combination of security constraints in Eclipse Jetty. Specifically, when two or more security constraints have the same http-method-omission set and no url-patterns, they are not combined properly according to the Jakarta Servlet Specification. This can result in later http-method-omission sets overriding previous constraints with the same http-method-omission set.

Defensive priority

Defenders should prioritize reviewing and updating their Jetty configurations to ensure proper constraint combination and verify the applicability of this vulnerability to their specific deployments.

Recommended defensive actions

• Review and update Jetty configurations to ensure proper security constraint combination.
• Verify the applicability of this vulnerability to specific deployments.
• Monitor for any official patches or updates from the vendor.
• Perform a thorough review of current security configurations to identify potential exposure.
• Implement compensating controls for exposed systems while remediation is scheduled and verified.
• Conduct an asset inventory to identify all affected Jetty deployments.
• Track exceptions and retest remediated assets to ensure vulnerability resolution.

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, including its description and CVSS score. However, specific version information and detailed exploitation scenarios are not provided in the source corpus.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.