{"id":86612,"date":"2026-03-05T09:37:59","date_gmt":"2026-03-05T09:37:59","guid":{"rendered":""},"modified":"-0001-11-30T00:00:00","modified_gmt":"-0001-11-30T06:00:00","slug":"cve-2024-47252-untrusted-ssl-tls-client-can-insert-escape-characters-in-apache-http-server-log-files","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2024-47252-untrusted-ssl-tls-client-can-insert-escape-characters-in-apache-http-server-log-files\/","title":{"rendered":"<strong>CVE-2024-47252: Untrusted SSL\/TLS Client Can Insert Escape Characters in Apache HTTP Server Log Files<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The vulnerability CVE-2024-47252 affects Apache HTTP Server 2.4.63 and earlier versions. An untrusted SSL\/TLS client can exploit this weakness to insert escape characters into log files in certain configurations. This can potentially lead to a system compromise or data leakage, making it a critical issue for administrators and security personnel managing Apache HTTP Server environments.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2024-47252<br \/>\nSeverity: High (7.5 CVSS)<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-2586182530\" 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>Apache HTTP Server | 2.4.63 and earlier<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The vulnerability is due to insufficient escaping of user-supplied data in mod_ssl. In a logging configuration where CustomLog is used with &#8220;%{varname}x&#8221; or &#8220;%{varname}c&#8221; to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl. This allows an untrusted SSL\/TLS client to insert escape characters into log files, leading to unsanitized data appearing in the log files.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-218119353\" 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>This is a theoretical example of how a HTTP request might exploit the vulnerability:<\/p>\n<pre><code class=\"\" data-line=\"\">GET \/ HTTP\/1.1\nHost: vulnerable.server.com\nSSL_TLS_SNI: www.vulnerable.server.com\\r\\nInjected_Header: Malicious_Content<\/code><\/pre>\n<p>In the above example, the attacker inserts a carriage return and newline characters in the SSL_TLS_SNI field, followed by a malicious header. This would then be logged as is by the server, potentially leading to various forms of exploits, including log injection attacks.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The vulnerability CVE-2024-47252 affects Apache HTTP Server 2.4.63 and earlier versions. An untrusted SSL\/TLS client can exploit this weakness to insert escape characters into log files in certain configurations. This can potentially lead to a system compromise or data leakage, making it a critical issue for administrators and security personnel managing Apache HTTP Server [&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-86612","post","type-post","status-publish","format-standard","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/86612","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=86612"}],"version-history":[{"count":0,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/86612\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=86612"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=86612"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=86612"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=86612"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=86612"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=86612"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=86612"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=86612"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=86612"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}