{"id":86038,"date":"2025-12-14T13:18:01","date_gmt":"2025-12-14T13:18:01","guid":{"rendered":""},"modified":"-0001-11-30T00:00:00","modified_gmt":"-0001-11-30T06:00:00","slug":"cve-2025-7403-unsafe-handling-in-bt-conn-tx-processor-resulting-in-write-before-zero-vulnerability","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-7403-unsafe-handling-in-bt-conn-tx-processor-resulting-in-write-before-zero-vulnerability\/","title":{"rendered":"<strong>CVE-2025-7403: Unsafe Handling in bt_conn_tx_processor Resulting in Write-Before-Zero Vulnerability<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>CVE-2025-7403 is a critical vulnerability affecting the handling of bt_conn_tx_processor. This vulnerability enables an attacker to cause a use-after-free condition, leading to a write-before-zero scenario. The issue arises from an error in handling, which allows the attacker to control the written four bytes, causing precise memory corruption. This vulnerability is critical as it poses potential risks for system compromise and data leakage.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-7403<br \/>\nSeverity: High (7.6 CVSS score)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: Potential system compromise or data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-3449700553\" 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>bt_conn_tx_processor | All versions to current<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The exploitation of this vulnerability involves an attacker taking advantage of the unsafe handling in bt_conn_tx_processor. The attacker can corrupt the memory by controlling the written four bytes due to a use-after-free condition. This precise memory corruption could lead to potential system compromise or data leakage, primarily if the corrupted data is sensitive or critical to system operations.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-502667847\" 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>A conceptual example of how an attacker might exploit this vulnerability could be through a malicious payload sent to the vulnerable system:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/bt_conn_tx_processor\/endpoint HTTP\/1.1\nHost: target.example.com\nContent-Type: application\/json\n{\n&quot;malicious_payload&quot;: &quot;4_bytes_controlled_data&quot;\n}<\/code><\/pre>\n<p>In the above example, &#8220;4_bytes_controlled_data&#8221; represents the four bytes of data that the attacker can control and which the vulnerable system would write before zero due to the use-after-free condition, thereby exploiting the vulnerability.<\/p>\n<p><strong>Mitigation<\/strong><\/p>\n<p>To mitigate this vulnerability, users should apply the vendor patch as soon as it becomes available. In the meantime, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can provide temporary mitigation by detecting and blocking attempts to exploit this vulnerability.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview CVE-2025-7403 is a critical vulnerability affecting the handling of bt_conn_tx_processor. This vulnerability enables an attacker to cause a use-after-free condition, leading to a write-before-zero scenario. The issue arises from an error in handling, which allows the attacker to control the written four bytes, causing precise memory corruption. This vulnerability is critical as it poses [&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-86038","post","type-post","status-publish","format-standard","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/86038","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=86038"}],"version-history":[{"count":0,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/86038\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=86038"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=86038"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=86038"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=86038"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=86038"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=86038"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=86038"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=86038"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=86038"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}