CVE-2026-18661
Description
A flaw was found in Eclipse Jetty. This vulnerability allows a remote, unauthenticated attacker to bypass access controls, leading to unauthorized information disclosure and potential data modification. When an application combines servlet security annotations with deployment descriptor configuration, Jetty fails to properly enforce security constraints across servlets configured with multiple URL patterns when constraints apply only to a subset of those paths. Consequently, an attacker can access restricted endpoints without satisfying the intended authorization checks.
Statement
This vulnerability is rated as Important because remote unauthenticated actors can bypass access restrictions to expose confidential data or alter state without required credentials. In Red Hat products utilizing embedded Jetty runtimes, exposure depends on deployed applications configuring a servlet with multiple URI mappings while defining security boundaries in the deployment descriptor for only a subset of those routes. Applications that define authorization policies uniformly across all path bindings or rely entirely on a single security specification mechanism are not exposed to this bypass.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 8.2 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | Low | N/A | N/A |
| Availability Impact | None | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Understanding the Weakness (CWE)
Confidentiality,Integrity,Availability,Access Control
Technical Impact: Read Application Data; Modify Application Data; Execute Unauthorized Code or Commands; Gain Privileges or Assume Identity
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
