{"id":38861,"date":"2025-05-17T09:18:11","date_gmt":"2025-05-17T09:18:11","guid":{"rendered":""},"modified":"2025-06-23T05:17:59","modified_gmt":"2025-06-23T11:17:59","slug":"cve-2025-4496-critical-buffer-overflow-vulnerability-in-totolink-routers","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-4496-critical-buffer-overflow-vulnerability-in-totolink-routers\/","title":{"rendered":"<strong>CVE-2025-4496: Critical Buffer Overflow Vulnerability in TOTOLINK Routers<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>A critical vulnerability, identified as CVE-2025-4496, has been discovered affecting a range of TOTOLINK router models. The vulnerability lies in the CloudACMunualUpdate function of the file \/cgi-bin\/cstecgi.cgi and can potentially lead to a system compromise or data leakage. This <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-32310-privilege-escalation-vulnerability-in-thememove-quickcal-due-to-csrf\/\"  data-wpil-monitor-id=\"50482\">vulnerability has been marked crucial due<\/a> to its high CVSS Severity Score and its potential for remote exploitation. As the exploit has been publicly disclosed, it poses a significant risk to all users of the affected router models.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-4496<br \/>\nSeverity: Critical (8.8 CVSS Score)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4372-webaudio-heap-corruption-in-google-chrome-a-potential-gateway-to-system-compromise-and-data-leakage\/\"  data-wpil-monitor-id=\"43800\">System Compromise and Data<\/a> Leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-4156828173\" 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-2025-5901-buffer-overflow-vulnerability-in-totolink-t10-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"60506\">TOTOLINK T10<\/a> | 4.1.8cu.5241_B20210927<br \/>\nTOTOLINK A3100R| 4.1.8cu.5241_B20210927<br \/>\nTOTOLINK A950RG | 4.1.8cu.5241_B20210927<br \/>\nTOTOLINK A800R | 4.1.8cu.5241_B20210927<br \/>\nTOTOLINK N600R | 4.1.8cu.5241_B20210927<br \/>\nTOTOLINK A3000RU | 4.1.8cu.5241_B20210927<br \/>\nTOTOLINK A810R | 4.1.8cu.5241_B20210927<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47549-critical-unrestricted-file-upload-vulnerability-in-themefic-beaf\/\"  data-wpil-monitor-id=\"43894\">vulnerability revolves around the CloudACMunualUpdate function in the \/cgi-bin\/cstecgi.cgi file<\/a>. The FileName argument, when manipulated, can lead to a <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4342-critical-buffer-overflow-vulnerability-in-d-link-dir-600l\/\"  data-wpil-monitor-id=\"43481\">buffer overflow<\/a> condition. This could potentially allow an attacker to <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2023-49123-code-execution-vulnerability-in-solid-edge-se2023\/\"  data-wpil-monitor-id=\"43555\">execute arbitrary code<\/a> on the system or cause the system to crash, leading to a denial of service. The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-32819-remote-attacker-bypassing-path-traversal-checks-in-sma100\/\"  data-wpil-monitor-id=\"44107\">attack can be initiated remotely<\/a>, without requiring any user interaction or special privileges.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-767098988\" 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>As a conceptual example, an attacker could exploit this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47462-cross-site-request-forgery-vulnerability-in-ohidul-islam-challan-leading-to-privilege-escalation\/\"  data-wpil-monitor-id=\"43658\">vulnerability by sending a specially crafted HTTP request<\/a> to the target system. It could look something like this:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/cgi-bin\/cstecgi.cgi\/CloudACMunualUpdate HTTP\/1.1\nHost: target.example.com\nContent-Type: application\/json\n{ &quot;FileName&quot;: &quot;malicious_payload...&quot; }<\/code><\/pre>\n<p>In this example, the &#8220;FileName&#8221; argument is manipulated with a malicious payload that causes a <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4343-critical-buffer-overflow-vulnerability-in-d-link-dir-600l\/\"  data-wpil-monitor-id=\"43485\">buffer overflow<\/a>, leading to the unintended consequences.<\/p>\n<p><strong>Mitigation<\/strong><\/p>\n<p>Users of the affected TOTOLINK routers are strongly advised to apply the vendor patch as soon as it becomes available. In the meantime, implementing a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as a temporary mitigation measure to guard against <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2023-49129-stack-overflow-vulnerability-in-solid-edge-se2023-allows-potential-system-compromise\/\"  data-wpil-monitor-id=\"43502\">potential attacks exploiting this vulnerability<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview A critical vulnerability, identified as CVE-2025-4496, has been discovered affecting a range of TOTOLINK router models. The vulnerability lies in the CloudACMunualUpdate function of the file \/cgi-bin\/cstecgi.cgi and can potentially lead to a system compromise or data leakage. This vulnerability has been marked crucial due to its high CVSS Severity Score and its potential [&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":[],"product":[],"attack_vector":[86,87],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-38861","post","type-post","status-publish","format-standard","hentry","category-uncategorized","attack_vector-buffer-overflow","attack_vector-dos"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/38861","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=38861"}],"version-history":[{"count":10,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/38861\/revisions"}],"predecessor-version":[{"id":54234,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/38861\/revisions\/54234"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=38861"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=38861"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=38861"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=38861"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=38861"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=38861"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=38861"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=38861"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=38861"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}