{"id":59781,"date":"2025-07-31T17:19:07","date_gmt":"2025-07-31T17:19:07","guid":{"rendered":""},"modified":"2025-09-27T02:05:14","modified_gmt":"2025-09-27T08:05:14","slug":"cve-2025-8138-critical-buffer-overflow-vulnerability-in-totolink-a702r","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-8138-critical-buffer-overflow-vulnerability-in-totolink-a702r\/","title":{"rendered":"<strong>CVE-2025-8138: Critical Buffer Overflow Vulnerability in TOTOLINK A702R<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The Common Vulnerabilities and Exposures (CVE) system has recently detailed a critical vulnerability with the identifier CVE-2025-8138, found in TOTOLINK A702R version 4.0.0-B20230721.1521. This vulnerability, if exploited, can lead to serious security breaches, system compromise, and potential data leakage. It is of critical importance to any individual or organization using the affected <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49416-critical-php-remote-file-inclusion-vulnerability-in-fastw3b-llc-fw-gallery\/\"  data-wpil-monitor-id=\"66087\">TOTOLINK<\/a> product to understand and mitigate this vulnerability as soon as possible.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-8138<br \/>\nSeverity: Critical (CVSS: 8.8)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-31278-memory-corruption-vulnerability-with-potential-system-compromise\/\"  data-wpil-monitor-id=\"70684\">Potential system<\/a> compromise or data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-1932739365\" 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-2025-9779-totolink-a702r-buffer-overflow-vulnerability-in-the-function-sub-4162dc\/\"  data-wpil-monitor-id=\"85109\">TOTOLINK A702R<\/a> | 4.0.0-B20230721.1521<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52809-php-remote-file-inclusion-vulnerability-in-national-weather-service-alerts\/\"  data-wpil-monitor-id=\"66088\">vulnerability resides in an unknown functionality of the file<\/a> \/boafrm\/formOneKeyAccessButton in the HTTP POST Request Handler component of the TOTOLINK A702R firmware. The exploitation of this vulnerability involves the manipulation of the &#8216;submit-url&#8217; argument, which can cause a <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-7596-critical-remote-buffer-overflow-vulnerability-in-tenda-fh1205\/\"  data-wpil-monitor-id=\"66442\">buffer overflow<\/a>. This <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-8243-critical-buffer-overflow-vulnerability-in-totolink-x15-http-post-request-handler\/\"  data-wpil-monitor-id=\"66761\">buffer overflow<\/a> may then result in undefined behavior, potentially leading to system compromise and data leakage.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-515147521\" 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>An attacker might exploit this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-36845-server-side-request-forgery-ssrf-vulnerability-in-eveo-urve-web-manager\/\"  data-wpil-monitor-id=\"70683\">vulnerability by sending a maliciously crafted HTTP POST request<\/a> similar to the following:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/boafrm\/formOneKeyAccessButton HTTP\/1.1\nHost: target.example.com\nContent-Type: application\/x-www-form-urlencoded\nsubmit-url=www.example.com%00[insert malicious payload here]<\/code><\/pre>\n<p>In this example, the &#8216;submit-url&#8217; argument is appended with a null byte (%00) followed by a malicious payload. This causes an <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-7597-critical-stack-based-buffer-overflow-vulnerability-in-tenda-ax1803-1-0-0-1\/\"  data-wpil-monitor-id=\"66972\">overflow in the buffer<\/a> that stores the &#8216;submit-url&#8217; data, which can lead to unintended consequences, potentially compromising the system and leaking data.<\/p>\n<p><strong>Mitigation Guidance<\/strong><\/p>\n<p>It is highly recommended to apply a vendor-supplied patch as soon as possible. If a patch is not immediately available or feasible, consider using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to temporarily mitigate the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-44955-critical-vulnerability-in-ruckus-network-director-allows-jail-users-to-gain-root-access\/\"  data-wpil-monitor-id=\"76011\">vulnerability by monitoring network<\/a> traffic and blocking or alerting on suspicious activity.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The Common Vulnerabilities and Exposures (CVE) system has recently detailed a critical vulnerability with the identifier CVE-2025-8138, found in TOTOLINK A702R version 4.0.0-B20230721.1521. This vulnerability, if exploited, can lead to serious security breaches, system compromise, and potential data leakage. It is of critical importance to any individual or organization using the affected TOTOLINK product [&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],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-59781","post","type-post","status-publish","format-standard","hentry","category-uncategorized","attack_vector-buffer-overflow"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59781","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=59781"}],"version-history":[{"count":7,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59781\/revisions"}],"predecessor-version":[{"id":77896,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59781\/revisions\/77896"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=59781"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=59781"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=59781"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=59781"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=59781"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=59781"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=59781"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=59781"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=59781"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}