{"cve":"CVE-2025-21597","nvd":{"published":"2025-04-09T20:15:26.100","modified":"2026-06-17T08:43:49.037","status":"Analyzed","description":"An Improper Check for Unusual or Exceptional Conditions vulnerability in routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, logically adjacent BGP peer to cause Denial of Service (DoS).\n\nOn all Junos OS and Junos OS Evolved platforms, when BGP rib-sharding and update-threading are configured, and a BGP peer flap is done with specific timing, rpd crashes and restarts. Continuous peer flapping at specific time intervals will result in a sustained Denial of Service (DoS) condition.\n\nThis issue affects eBGP and iBGP, in both IPv4 and IPv6 implementations.  This issue requires a remote attacker to have at least one established BGP session. The issue can occur with or without logical-systems enabled.\n\nThis issue affects:\nJunos OS:\n\n\n\n  *  All versions before 20.4R3-S8,\n  *  21.2 versions before 21.2R3-S6,\n\n  *  21.3 versions before 21.3R3-S5,\n  *  21.4 versions before 21.4R3-S4,\n  *  22.1 versions before 22.1R3-S3,\n  *  22.2 versions before 22.2R3-S1,\n  *  22.3 versions before 22.3R3,\n  *  22.4 versions before 22.4R3.\n\n\nJunos OS Evolved:\n\n\n\n  *  All versions before 21.2R3-S6-EVO,\n  *  21.3-EVO versions before 21.3R3-S5-EVO,\n  *  21.4-EVO versions before 21.4R3-S4-EVO,\n  *  22.1-EVO versions before 22.1R3-S3-EVO,\n  *  22.2-EVO versions before :22.2R3-S1-EVO,\n  *  22.3-EVO versions before 22.3R3-EVO,\n  *  22.4-EVO versions before 22.4R3-EVO.","cvss_v4":{"vector":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/R:A","score":6.0},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.3},"cwes":["CWE-754"],"references":["https://kb.juniper.net/JSA96451"],"products":["juniper:junos","juniper:junos_os_evolved"],"source":"nvd","synced_at":"2026-10-19T22:00:57.946988208+00:00"},"epss":{"cve":"CVE-2025-21597","score":0.00247,"percentile":0.16048,"date":"2026-10-31"},"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."]}