Vulnerability Database

357,869

Total vulnerabilities in the database

CVE-2026-57054 — juniper / junos

Use of Incorrectly-Resolved Name or Reference

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.
  • Published: Jul 9, 2026
  • Updated: Jul 10, 2026
  • CVE: CVE-2026-57054
  • Severity: Medium
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Medium
  • Score: 5.8
  • AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

CWEs:

Software From Fixed in
juniper / junos - 23.2
juniper / junos 23.2 23.2.x
juniper / junos 23.2-r1 23.2-r1.x
juniper / junos 23.2-r1-s1 23.2-r1-s1.x
juniper / junos 23.2-r1-s2 23.2-r1-s2.x
juniper / junos 23.2-r2 23.2-r2.x
juniper / junos 23.2-r2-s1 23.2-r2-s1.x
juniper / junos 23.2-r2-s2 23.2-r2-s2.x
juniper / junos 23.2-r2-s3 23.2-r2-s3.x
juniper / junos 23.2-r2-s4 23.2-r2-s4.x
juniper / junos 23.2-r2-s5 23.2-r2-s5.x
juniper / junos 23.2-r2-s6 23.2-r2-s6.x
juniper / junos 23.4 23.4.x
juniper / junos 23.4-r1 23.4-r1.x
juniper / junos 23.4-r1-s1 23.4-r1-s1.x
juniper / junos 23.4-r1-s2 23.4-r1-s2.x
juniper / junos 23.4-r2 23.4-r2.x
juniper / junos 23.4-r2-s1 23.4-r2-s1.x
juniper / junos 23.4-r2-s2 23.4-r2-s2.x
juniper / junos 23.4-r2-s3 23.4-r2-s3.x
juniper / junos 23.4-r2-s4 23.4-r2-s4.x
juniper / junos 23.4-r2-s5 23.4-r2-s5.x
juniper / junos 23.4-r2-s6 23.4-r2-s6.x
juniper / junos 23.4-r2-s7 23.4-r2-s7.x
juniper / junos 24.2 24.2.x
juniper / junos 24.2-r1 24.2-r1.x
juniper / junos 24.2-r1-s1 24.2-r1-s1.x
juniper / junos 24.2-r1-s2 24.2-r1-s2.x
juniper / junos 24.2-r2 24.2-r2.x
juniper / junos 24.2-r2-s1 24.2-r2-s1.x
juniper / junos 24.2-r2-s2 24.2-r2-s2.x
juniper / junos 24.2-r2-s3 24.2-r2-s3.x
juniper / junos 24.2-r2-s4 24.2-r2-s4.x
juniper / junos 24.4 24.4.x
juniper / junos 24.4-r1 24.4-r1.x
juniper / junos 24.4-r1-s2 24.4-r1-s2.x
juniper / junos 24.4-r1-s3 24.4-r1-s3.x
juniper / junos 24.4-r2 24.4-r2.x
juniper / junos 24.4-r2-s1 24.4-r2-s1.x
juniper / junos 24.4-r2-s2 24.4-r2-s2.x
juniper / junos 24.4-r2-s3 24.4-r2-s3.x
juniper / junos 25.2 25.2.x
juniper / junos 25.2-r1 25.2-r1.x
juniper / junos 25.2-r1-s1 25.2-r1-s1.x
juniper / junos 25.2-r1-s2 25.2-r1-s2.x
juniper / junos 25.2-r2 25.2-r2.x
juniper / junos 25.4 25.4.x
juniper / junos 25.4-r1 25.4-r1.x
juniper / junos 25.4-r1-s1 25.4-r1-s1.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.