{"cve":"CVE-2025-59957","nvd":{"published":"2025-10-09T16:15:45.657","modified":"2026-10-08T13:10:00.200","status":"Analyzed","description":"An Origin Validation Error vulnerability in an insufficient protected file of Juniper Networks Junos OS on EX4600 Series and QFX5000 Series allows an unauthenticated attacker with physical access to the device to create a backdoor which allows complete control of the system.\n\nWhen a device isn't configured with a root password, an attacker can modify a specific file. It's contents will be added to the Junos configuration of the device without being visible. This allows for the addition of any configuration unknown \n\nto the actual operator, which includes users, IP addresses and other configuration which could allow unauthorized access to the device.\nThis exploit is persistent across reboots and even zeroization.\n\nThe indicator of compromise is a modified /etc/config/<platform>-defaults[-flex].conf file. Review that file for unexpected configuration statements, or compare it to an unmodified version which can be extracted from the original Juniper software image file. For details on the extraction procedure please contact Juniper Technical Assistance Center (JTAC).\n\nTo restore the device to a trusted initial configuration the system needs to be reinstalled from physical media. \n\nThis issue affects Junos OS on EX4600 Series and QFX5000 Series:\n\n\n\n  *  All versions before 21.4R3,\n  *  22.2 versions before 22.2R3-S3.","cvss_v4":{"vector":"CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/AU:N/R:U/RE:H","score":7.0},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":6.8},"cwes":["CWE-346"],"references":["https://support.juniper.net/support/requesting-support/","https://supportportal.juniper.net/JSA103146","https://supportportal.juniper.net/s/article/EX-QFX-Procedure-to-format-install-QFX5K-device-using-a-USB"],"products":["juniper:junos"],"source":"nvd","synced_at":"2026-10-19T22:11:26.888974865+00:00"},"epss":{"cve":"CVE-2025-59957","score":0.00184,"percentile":0.07932,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}