This vulnerability (CWE-706) in Juniper Networks Junos OS on MX Series involves the use of an incorrectly-resolved name or reference in the URL filtering plugin. When web filtering is enabled, an attacker can send a specially formatted URL that bypasses the filtering mechanism, causing the request to be forwarded despite blocking configurations. This results in unauthorized access to downstream resources that are intended to be unreachable. The affected versions include all releases before 23.2R2-S7, 23.4 versions before 23.4R2-S8, 24.2 versions before 24.2R2-S5, 24.4 versions before 24.4R2-S4, 25.2 versions before 25.2R2-S1, and 25.4 versions before 25.4R1-S2 and 25.4R2.

An unauthenticated attacker can bypass configured web filtering on MX Series devices running vulnerable Junos OS versions, allowing access to downstream network resources that should be blocked. This can lead to unauthorized information access or network traversal but does not impact confidentiality or availability directly according to the CVSS vector (no confidentiality loss, limited integrity impact, no availability impact).

No explicit vendor advisory or patch links are provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is applied, consider disabling or restricting URL filtering on affected MX Series devices or applying network-level controls to limit exposure. Monitor Juniper Networks advisories for official patches or updates.