CVE-2026-57031
MEDIUMJunos OS: MX Series: For subscribers configured on static interfaces, input filters are not in effect
Title source: cnaDescription
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.
References (1)
Core 1
Core References
Vendor Advisory vendor-advisory
https://supportportal.juniper.net/JSA110091
Scores
CVSS v3
4.7
EPSS
0.0015
EPSS Percentile
4.8%
Attack Vector
ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-754
Status
published
Products (5)
Juniper Networks/Junos OS
23.2R2-S1 - 23.2R2-S7
Juniper Networks/Junos OS
23.4R2 - 23.4R2-S7
Juniper Networks/Junos OS
24.2 - 24.2R2-S3
Juniper Networks/Junos OS
24.4 - 24.4R2-S2
Juniper Networks/Junos OS
25.2 - 25.2R2
Published
Jul 09, 2026
Tracked Since
Jul 10, 2026