{"cve":"CVE-2024-39562","nvd":{"published":"2024-07-10T23:15:13.670","modified":"2026-06-17T07:42:14.270","status":"Analyzed","description":"A Missing Release of Resource after Effective Lifetime vulnerability the xinetd process, responsible for spawning SSH daemon (sshd) instances, of Juniper Networks Junos OS Evolved allows an unauthenticated network-based attacker to cause a Denial of Service (DoS) by blocking SSH access for legitimate users.  Continued receipt of these connections will create a sustained Denial of Service (DoS) condition.\n\nThe issue is triggered when a high rate of concurrent SSH requests are received and terminated in a specific way, causing xinetd to crash, and leaving defunct sshd processes. Successful exploitation of this vulnerability blocks both SSH access as well as services which rely upon SSH, such as SFTP, and Netconf over SSH.\n\nOnce the system is in this state, legitimate users will be unable to SSH to the device until service is manually restored.  See WORKAROUND section below.\n\nAdministrators can monitor an increase in defunct sshd processes by utilizing the CLI command:\n\n  > show system processes | match sshd\n  root     25219 30901  0 Jul16 ?        00:00:00 [sshd] <defunct>\n\nThis issue affects Juniper Networks Junos OS Evolved:\n  *  All versions prior to 21.4R3-S7-EVO\n  *  22.3-EVO versions prior to 22.3R2-S2-EVO, 22.3R3-S2-EVO;\n  *  22.4-EVO versions prior to 22.4R3-EVO;\n  *  23.2-EVO versions prior to 23.2R2-EVO.\n\n\n\nThis issue does not affect Juniper Networks Junos OS Evolved 22.1-EVO nor 22.2-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:N","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-772"],"references":["https://supportportal.juniper.net/JSA75724","https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","https://supportportal.juniper.net/JSA75724","https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"],"products":["juniper:junos_os_evolved"],"source":"nvd","synced_at":"2026-10-19T21:52:42.518321223+00:00"},"epss":{"cve":"CVE-2024-39562","score":0.00431,"percentile":0.37291,"date":"2026-11-01"},"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."]}