{"id":64257,"date":"2025-08-23T06:05:59","date_gmt":"2025-08-23T06:05:59","guid":{"rendered":""},"modified":"2025-08-31T18:37:26","modified_gmt":"2025-09-01T00:37:26","slug":"cve-2025-20133-remote-access-ssl-vpn-vulnerability-in-cisco-secure-firewall-asa-software-and-secure-ftd-software","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-20133-remote-access-ssl-vpn-vulnerability-in-cisco-secure-firewall-asa-software-and-secure-ftd-software\/","title":{"rendered":"<strong>CVE-2025-20133: Remote Access SSL VPN Vulnerability in Cisco Secure Firewall ASA Software and Secure FTD Software<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>A critical vulnerability, designated as CVE-2025-20133, has been identified within the Remote Access SSL VPN feature of Cisco Secure Firewall ASA Software and Secure FTD Software. This vulnerability could potentially allow an unauthenticated, remote attacker to render the device unresponsive, thereby triggering a Denial of Service (DoS) condition.<br \/>\nThis vulnerability is of high importance, particularly for businesses and corporations using <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-20253-critical-vulnerability-in-ikev2-feature-of-cisco-software-could-lead-to-denial-of-service-dos-attack\/\"  data-wpil-monitor-id=\"76175\">Cisco<\/a> Secure Firewall ASA Software and Secure FTD Software. The successful exploitation of this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-33075-a-critical-windows-installer-vulnerability-that-leads-to-privilege-elevation\/\"  data-wpil-monitor-id=\"72399\">vulnerability could ultimately lead<\/a> to system compromise or data leakage, posing significant risks to data integrity and business continuity.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-20133<br \/>\nSeverity: High (8.6 on the CVSS scale)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: Successful exploitation could lead to system disruption (DoS condition) and potential system compromise or <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-53495-unauthorized-access-data-leakage-in-wikimedia-foundation-mediawiki-abusefilter-extension\/\"  data-wpil-monitor-id=\"72473\">data leakage<\/a>.<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-2512828429\" 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: 720px;\">\r\n  <h2 style=\"margin-top: 0; font-size: 22px; font-weight: 600; display: flex; align-items: center; letter-spacing: -0.02em;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"display: inline-flex; align-items: center; margin-right: 10px;\">\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: 42px; height: 42px;\" \/>\r\n    <\/a>\r\n    Share secrets securely\r\n  <\/h2>\r\n\r\n  <p style=\"margin-bottom: 14px; color: #d1d5db;\">\r\n    Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.\r\n  <\/p>\r\n\r\n  <p style=\"margin-bottom: 18px; color: #a1a1aa;\">\r\n    Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.\r\n  <\/p>\r\n\r\n  <ul style=\"list-style: none; padding-left: 0; margin-bottom: 24px; color: #e4e4e7;\">\r\n    <li style=\"margin-bottom: 8px;\">\u2022 Encrypted identity<\/li>\r\n    <li style=\"margin-bottom: 8px;\">\u2022 Private Spaces for organizations and teams<\/li>\r\n    <li style=\"margin-bottom: 8px;\">\u2022 End-to-end encrypted chat, calls, files, and notes<\/li>\r\n    <li style=\"margin-bottom: 8px;\">\u2022 Sensitive AI work and protected collaboration<\/li>\r\n    <li>\u2022 Built for information that cannot leak<\/li>\r\n  <\/ul>\r\n\r\n  <p style=\"font-style: italic; font-weight: 600; margin-bottom: 24px; color: #ffffff;\">\r\n    Our mission is to secure human work alongside AI.\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: 8px; font-weight: 500;\">\r\n      Download Ameeba\r\n    <\/a>\r\n\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"border: 1px solid #ffffff; color: #ffffff; padding: 10px 20px; text-decoration: none; border-radius: 8px; font-weight: 500;\">\r\n      Learn More\r\n    <\/a>\r\n  <\/div>\r\n<\/div><\/div>\n<p>Product | Affected Versions<\/p>\n<p><a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-20136-denial-of-service-vulnerability-in-cisco-secure-firewall-asa-and-ftd-software\/\"  data-wpil-monitor-id=\"76911\">Cisco Secure Firewall ASA<\/a> Software | All versions preceding the vendor patch<br \/>\n<a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-20217-denial-of-service-vulnerability-in-snort-3-detection-engine-of-cisco-secure-firewall-threat-defense-software\/\"  data-wpil-monitor-id=\"76925\">Cisco Secure<\/a> FTD Software | All versions preceding the vendor patch<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The vulnerability stems from ineffective validation of user-supplied input during the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-53499-critical-unauthorized-access-vulnerability-in-wikimedia-foundation-mediawiki-abusefilter-extension\/\"  data-wpil-monitor-id=\"72767\">Remote<\/a> Access SSL VPN authentication process. An attacker can exploit this vulnerability by sending a specially crafted request to the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-30133-device-pairing-bypass-vulnerability-in-iroad-dashcam-fx2-devices\/\"  data-wpil-monitor-id=\"75649\">VPN<\/a> service on an affected device. This malformed request, when processed, causes the device to stop responding to <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47955-windows-remote-access-connection-manager-privilege-escalation-vulnerability\/\"  data-wpil-monitor-id=\"74001\">Remote Access<\/a> SSL VPN authentication requests, ultimately leading to a DoS condition.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-1134504306\" 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>Below is a conceptual HTTP request example that could <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-30327-integer-overflow-vulnerability-in-incopy-leading-to-potential-arbitrary-code-execution\/\"  data-wpil-monitor-id=\"73698\">potentially exploit the vulnerability<\/a>:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/vpn_authenticate HTTP\/1.1\nHost: target_device_IP\nContent-Type: application\/json\n{ &quot;username&quot;: &quot;valid_user&quot;, &quot;password&quot;: &quot;malicious_payload&quot; }<\/code><\/pre>\n<p>In this example, the &#8220;malicious_payload&#8221; is designed to exploit the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-43275-critical-race-condition-vulnerability-in-macos\/\"  data-wpil-monitor-id=\"71652\">vulnerability by triggering the DoS condition<\/a>. The actual form and specifics of the &#8220;malicious_payload&#8221; would depend on the internal workings of the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-20251-critical-vulnerability-in-cisco-secure-firewall-software-s-remote-access-ssl-vpn-service\/\"  data-wpil-monitor-id=\"81685\">SSL VPN<\/a> feature, which are not publicly disclosed for security reasons.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview A critical vulnerability, designated as CVE-2025-20133, has been identified within the Remote Access SSL VPN feature of Cisco Secure Firewall ASA Software and Secure FTD Software. This vulnerability could potentially allow an unauthenticated, remote attacker to render the device unresponsive, thereby triggering a Denial of Service (DoS) condition. This vulnerability is of high importance, [&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":[1],"tags":[],"vendor":[96],"product":[],"attack_vector":[87],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-64257","post","type-post","status-publish","format-standard","hentry","category-uncategorized","vendor-cisco","attack_vector-dos"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/64257","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=64257"}],"version-history":[{"count":11,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/64257\/revisions"}],"predecessor-version":[{"id":74138,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/64257\/revisions\/74138"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=64257"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=64257"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=64257"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=64257"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=64257"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=64257"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=64257"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=64257"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=64257"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}