Riskcovery

CVE-2026-57031

Junos OS: MX Series: For subscribers configured on static interfaces, input filters are not in effect

State
Published
Severity
5.3 Medium
Published
Jul 9, 2026
Updated
Jul 10, 2026
Reserved
Jun 23, 2026

Read the record on cve.org

Description

An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on MX Series allows adjacent subscribers to bypass configured firewall filters.

On MX Series devices with MPC10/11, LC4800/9600, and MX304 with subscribers configured on static interfaces, ingress firewall filters are not enforced, so that neither protocol level nor upstream bandwidth limitation are in effect.

This issue affects Junos OS on MX with MPC10/11, LC4800/9600/4802, and MX304:

* 23.2 versions from 23.2R2-S1 before 23.2R2-S7, * 23.4 versions from 23.4R2 before 23.4R2-S7, * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S2, * 25.2 versions before 25.2R2.

Scores

CVSSScoreVectorSource
4.05.3 MediumCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/AU:Y/RE:Mjuniper
3.14.7 MediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Njuniper

Weaknesses

  • CWE-754 Improper Check for Unusual or Exceptional Conditions

Affected Products

ProductVersions
Junos OSJuniper Networks
  • 23.2R2-S1 to before 23.2R2-S7Affected
  • 23.4R2 to before 23.4R2-S7Affected
  • 24.2 to before 24.2R2-S3Affected
  • 24.4 to before 24.4R2-S2Affected
  • 25.2 to before 25.2R2Affected

References

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