{"cve":"CVE-2024-39555","nvd":{"published":"2024-07-10T23:15:11.863","modified":"2026-06-17T07:42:12.963","status":"Analyzed","description":"An Improper Handling of Exceptional Conditions vulnerability in the Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an attacker sending a specific malformed BGP update message to cause the session to reset, resulting in a Denial of Service (DoS).  Continued receipt and processing of these malformed BGP update messages will create a sustained Denial of Service (DoS) condition.\n\nUpon receipt of a BGP update message over an established BGP session containing a specifically malformed tunnel encapsulation attribute, when segment routing is enabled, internal processing of the malformed attributes within the update results in improper parsing of remaining attributes, leading to session reset:\n\nBGP SEND Notification code 3 (Update Message Error) subcode 1 (invalid attribute list)\n\nOnly systems with segment routing enabled are vulnerable to this issue.\n\nThis issue affects eBGP and iBGP, in both IPv4 and IPv6 implementations, and requires a remote attacker to have at least one established BGP session.\n\nThis issue affects:\n\nJunos OS: \n\n\n  *  All versions before 21.4R3-S8, \n  *  from 22.2 before 22.2R3-S4, \n  *  from 22.3 before 22.3R3-S3, \n  *  from 22.4 before 22.4R3-S3, \n  *  from 23.2 before 23.2R2-S1, \n  *  from 23.4 before 23.4R1-S2, 23.4R2.\n\n\nJunos OS Evolved: \n\n  *  All versions before 21.4R3-S8-EVO, \n  *  from 22.2-EVO before 22.2R3-S4-EVO, \n  *  from 22.3-EVO before 22.3R3-S3-EVO, \n  *  from 22.4-EVO before 22.4R3-S3-EVO, \n  *  from 23.2-EVO before 23.2R2-S1-EVO, \n  *  from 23.4-EVO before 23.4R1-S2-EVO, 23.4R2-EVO.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/R:A","score":8.7},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-755"],"references":["https://supportportal.juniper.net/JSA83015","https://supportportal.juniper.net/JSA83015"],"products":["juniper:junos","juniper:junos_os_evolved"],"source":"nvd","synced_at":"2026-10-19T21:52:42.518321223+00:00"},"epss":{"cve":"CVE-2024-39555","score":0.00498,"percentile":0.42739,"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."]}