CVE-2026-57031
Full vulnerability record from the local CVENow database.
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.
Severity
MEDIUM
CVSS score
5.3
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-09 22:17:08.827000
Last modified
2026-10-25 15:10:00.147000
View original CVE JSON
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"sourceIdentifier": "[email protected]",
"published": "2026-07-09T22:17:08.827",
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