{"id":56517,"date":"2025-07-01T22:56:36","date_gmt":"2025-07-01T22:56:36","guid":{"rendered":""},"modified":"2025-09-07T11:37:54","modified_gmt":"2025-09-07T17:37:54","slug":"cve-2025-6435-firefox-vulnerability-leading-to-potential-system-compromise-and-data-leakage","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-6435-firefox-vulnerability-leading-to-potential-system-compromise-and-data-leakage\/","title":{"rendered":"<strong>CVE-2025-6435: Firefox Vulnerability Leading to Potential System Compromise and Data Leakage<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>CVE-2025-6435 is a serious security vulnerability affecting versions of Firefox prior to 140. It stems from an issue in the browser&#8217;s Devtools, specifically within the Network tab&#8217;s &#8216;Save As&#8217; context menu option. This flaw could <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-4981-critical-file-extraction-vulnerability-in-mattermost-leading-to-potential-remote-code-execution\/\"  data-wpil-monitor-id=\"63066\">lead to a user inadvertently running a potentially<\/a> malicious executable, thereby compromising their system or leading to data leakage. Given the popularity of Firefox and the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-6510-critical-vulnerability-in-netgear-ex6100-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"63640\">potential widespread impact of this vulnerability<\/a>, it is crucial for users and administrators to understand the nature of this flaw and take necessary steps to mitigate it.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-6435<br \/>\nSeverity: High (CVSS score 8.1)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: Required<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-32878-critical-vulnerability-in-coros-pace-3-devices-leads-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"63178\">Potential system<\/a> compromise or data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-2935692745\" 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>Firefox | < 140\n\n<strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52950-unauthorized-access-exploitation-in-juniper-networks-security-director\/\"  data-wpil-monitor-id=\"79917\">exploit leverages the &#8216;Save As&#8217; function in the Network<\/a> tab of Firefox&#8217;s Devtools. When a user saves a response using this function, the resulting <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-32880-unencrypted-firmware-file-download-in-coros-pace-3-devices\/\"  data-wpil-monitor-id=\"62938\">file may not have the &#8216;.download<\/a>&#8216; extension. This could lead the user to mistake the file&#8217;s nature, potentially opening an executable file believing it to be an innocuous download. If this file contains malicious code, it could then be executed on the user&#8217;s system, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-5866-critical-vulnerability-in-rt-thread-5-1-0-potentially-leading-to-system-compromise-or-data-leakage\/\"  data-wpil-monitor-id=\"63799\">leading to compromise or data<\/a> leakage.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p>\n<p>A conceptual example of how this might be exploited could involve a malicious actor crafting a payload to be delivered through the browser&#8217;s network responses. The user, believing they&#8217;re saving a harmless file, could inadvertently save and execute this malicious payload. For illustrative purposes, a sample HTTP response might look like this:<\/p><div id=\"ameeb-1212037687\" 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<pre><code class=\"\" data-line=\"\">HTTP\/1.1 200 OK\nDate: Mon, 23 May 2025 22:38:34 GMT\nContent-Type: application\/octet-stream\nContent-Disposition: attachment; filename=&quot;example&quot;\n{ &quot;malicious_payload&quot;: &quot;...&quot; }<\/code><\/pre>\n<p>In this example, the malicious payload is embedded within the HTTP response. If saved and executed by the user, it could <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2024-7457-macos-authorization-model-exploit-leading-to-potential-mitm-attacks\/\"  data-wpil-monitor-id=\"79916\">lead to the exploitation<\/a> of CVE-2025-6435.<\/p>\n<p><strong>Mitigation<\/strong><\/p>\n<p>To mitigate this vulnerability, users should apply the vendor-supplied patch for Firefox. If for some reason this is not possible, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) could serve as a temporary mitigation measure. These <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-6370-critical-vulnerability-in-d-link-dir-619l-2-06b01-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"63377\">systems could potentially<\/a> identify and block malicious network responses based on known patterns of malicious activity. However, these should only be seen as temporary measures, and applying the official patch should be a top priority.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview CVE-2025-6435 is a serious security vulnerability affecting versions of Firefox prior to 140. It stems from an issue in the browser&#8217;s Devtools, specifically within the Network tab&#8217;s &#8216;Save As&#8217; context menu option. This flaw could lead to a user inadvertently running a potentially malicious executable, thereby compromising their system or leading to data leakage. [&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":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-56517","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/56517","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=56517"}],"version-history":[{"count":7,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/56517\/revisions"}],"predecessor-version":[{"id":72352,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/56517\/revisions\/72352"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=56517"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=56517"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=56517"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=56517"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=56517"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=56517"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=56517"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=56517"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=56517"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}