{"id":86115,"date":"2025-12-24T07:45:04","date_gmt":"2025-12-24T07:45:04","guid":{"rendered":""},"modified":"-0001-11-30T00:00:00","modified_gmt":"-0001-11-30T06:00:00","slug":"cve-2024-21606-double-free-vulnerability-in-juniper-networks-junos-os-leading-to-denial-of-service","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2024-21606-double-free-vulnerability-in-juniper-networks-junos-os-leading-to-denial-of-service\/","title":{"rendered":"<strong>CVE-2024-21606: Double Free Vulnerability in Juniper Networks Junos OS Leading to Denial of Service<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The vulnerability identified as CVE-2024-21606 is a critical issue that affects Juniper Networks Junos OS on SRX Series. This vulnerability, due to a Double Free issue, potentially allows an unauthenticated attacker to cause a Denial of Service (DoS) attack, posing a serious threat to businesses and organizations that rely on these systems for their operations.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2024-21606<br \/>\nSeverity: High (7.5)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: Potential system compromise or data leakage, leading to Denial of Service<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-4248572048\" class=\"ameeb-content-2 ameeb-entity-placement\"><div style=\"border-left: 4px solid #555; padding-left: 20px; margin: 48px 0; font-family: Roboto, sans-serif; color: #ffffff; line-height: 1.6; max-width: 700px;\">\r\n  <h2 style=\"margin-top: 0; font-size: 20px; font-weight: 600; display: flex; align-items: center;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"display: inline-flex; align-items: center; margin-right: 8px;\">\r\n      <img decoding=\"async\" src=\"https:\/\/www.ameeba.com\/blog\/wp-content\/uploads\/2025\/10\/Best-App-icon-Ameeba.png\" alt=\"Ameeba Chat Icon\" style=\"width: 40px; height: 40px;\" \/>\r\n    <\/a>\r\n    A new way to communicate\r\n  <\/h2>\r\n\r\n  <p style=\"margin-bottom: 12px;\">\r\n    Ameeba Chat is built on encrypted identity, not personal profiles.\r\n  <\/p>\r\n\r\n  <p style=\"margin-bottom: 16px;\">\r\n    Message, call, share files, and coordinate with identities kept separate.\r\n  <\/p>\r\n\r\n  <ul style=\"list-style: none; padding-left: 0; margin-bottom: 20px;\">\r\n    <li>\u2022 Encrypted identity<\/li>\r\n    <li>\u2022 Ameeba Chat authenticates access<\/li>\r\n    <li>\u2022 Aliases and categories<\/li>\r\n    <li>\u2022 End-to-end encrypted chat, calls, and files<\/li>\r\n    <li>\u2022 Secure notes for sensitive information<\/li>\r\n  <\/ul>\r\n\r\n  <p style=\"font-style: italic; font-weight: 600; margin-bottom: 24px;\">\r\n    Private communication, rethought.\r\n  <\/p>\r\n\r\n  <div style=\"display: flex; flex-wrap: wrap; gap: 12px;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\/download\" style=\"background-color: #ffffff; color: #000000; padding: 10px 20px; text-decoration: none; border-radius: 6px; font-weight: 500;\">Download Ameeba Chat<\/a>\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"border: 1px solid #ffffff; color: #ffffff; padding: 10px 20px; text-decoration: none; border-radius: 6px; font-weight: 500;\">Learn More<\/a>\r\n  <\/div>\r\n<\/div>\r\n<\/div>\n<p>Product | Affected Versions<\/p>\n<p>Junos OS on SRX Series | All versions earlier than 20.4R3-S8<br \/>\nJunos OS on SRX Series | 21.2 versions earlier than 21.2R3-S6<br \/>\nJunos OS on SRX Series | 21.3 versions earlier than 21.3R3-S5<br \/>\nJunos OS on SRX Series | 21.4 versions earlier than 21.4R3-S5<br \/>\nJunos OS on SRX Series | 22.1 versions earlier than 22.1R3-S3<br \/>\nJunos OS on SRX Series | 22.2 versions earlier than 22.2R3-S3<br \/>\nJunos OS on SRX Series | 22.3 versions earlier than 22.3R3-S1<br \/>\nJunos OS on SRX Series | 22.4 versions earlier than 22.4R2-S2, 22.4R3<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The exploit works by taking advantage of a Double Free vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX Series. In a remote access VPN scenario, if a &#8220;tcp-encap-profile&#8221; is configured and a sequence of specific packets is received, a flowd crash and restart will be observed, leading to a Denial of Service.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-285466575\" class=\"ameeb-content ameeb-entity-placement\"><div class=\"poptin-embedded\" data-id=\"f6b387694f681\"><\/div>\r\n\r\n\r\n\r\n\r\n\r\n<\/div>\n<p>While the exact details of the exploit are not provided, a conceptual example might involve sending a specific sequence of packets to a vulnerable endpoint. It might look something like this:<\/p>\n<pre><code class=\"\" data-line=\"\">import socket\ndef send_malicious_packets(target_ip, target_port):\n# Establish a connection\ns = socket.socket(socket.AF_INET, socket.SOCK_STREAM)\ns.connect((target_ip, target_port))\n# Send a sequence of specific packets\nfor packet in malicious_packet_sequence:\ns.send(packet)\n# Close the connection\ns.close()\n# Replace with the target IP and port\nsend_malicious_packets(&#039;192.0.2.0&#039;, 1234)<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Overview The vulnerability identified as CVE-2024-21606 is a critical issue that affects Juniper Networks Junos OS on SRX Series. This vulnerability, due to a Double Free issue, potentially allows an unauthenticated attacker to cause a Denial of Service (DoS) attack, posing a serious threat to businesses and organizations that rely on these systems for their [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"footnotes":""},"categories":[],"tags":[],"vendor":[],"product":[],"attack_vector":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-86115","post","type-post","status-publish","format-standard","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/86115","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/comments?post=86115"}],"version-history":[{"count":0,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/86115\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=86115"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=86115"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=86115"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=86115"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=86115"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=86115"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=86115"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=86115"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=86115"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}