CVE-2026-57054 Junos OS: MX Series: Web filtering doesn't block specifically formatted URLs

Medium 6.9 Published 9 Jul 2026 Updated 10 Jul 2026

Attackers can bypass web filtering on Juniper MX Series devices by using specially formatted URLs, accessing blocked resources.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-57054?

CVE-2026-57054 is a medium-severity vulnerability in Juniper Junos, published on 9 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A Use of Incorrectly-Resolved Name or Reference vulnerability in the URL filtering plugin of Juniper Networks Junos OS on MX Series allows an unauthenticated, network-based attacker to bypass web filtering and access downstream resources that should be unreachable.

If an MX Series device is configured with web filtering, and an attacker sends a request with a specifically formatted URL, this request will get forwarded despite the system being configured to block it. In turn, an attacker can access downstream resources that are expected to be unreachable.

This issue affects Junos OS on MX Series:

* all versions 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, * 25.4 versions before 25.4R1-S2, 25.4R2.

Weakness: CWE-706

Which versions are affected by CVE-2026-57054?

It affects 1 product.

Products include Juniper Junos.

How do I fix CVE-2026-57054?

No fix has been published for CVE-2026-57054 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-57054 being exploited?

There is no known exploitation of CVE-2026-57054 in the wild and no public exploit code.

All Juniper Junos vulnerabilities

Sources

Also known as GHSA-h62j-crg6-gvwf.