{"id":59912,"date":"2025-08-06T05:05:51","date_gmt":"2025-08-06T05:05:51","guid":{"rendered":""},"modified":"2025-09-16T07:09:16","modified_gmt":"2025-09-16T13:09:16","slug":"cve-2025-54576-oauth2-proxy-authentication-bypass-vulnerability","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-54576-oauth2-proxy-authentication-bypass-vulnerability\/","title":{"rendered":"<strong>CVE-2025-54576: OAuth2-Proxy Authentication Bypass Vulnerability<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>OAuth2-Proxy, an open-source reverse proxy middleware, is suffering from a critical vulnerability affecting versions 7.10.0 and below. This vulnerability can enable attackers to bypass authentication using the skip_auth_routes configuration option with regex patterns. Consequently, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-5835-droip-plugin-for-wordpress-unauthorized-access-and-modification-vulnerability\/\"  data-wpil-monitor-id=\"69956\">unauthorized users can gain access<\/a> to protected resources, leading to potential system compromise and data leakage. The issue is of significant concern to organizations that use OAuth2-Proxy as part of their security infrastructure, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-40741-stack-based-overflow-vulnerability-in-solid-edge-se2025-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"75857\">potentially impacting the integrity and confidentiality of their systems<\/a>.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-54576<br \/>\nSeverity: Critical (CVSS: 9.1)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-50160-heap-based-buffer-overflow-in-windows-rras-posing-system-compromise-risk\/\"  data-wpil-monitor-id=\"78584\">System compromise<\/a> or data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-1273701497\" 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>OAuth2-Proxy | 7.10.0 and below<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2022-43110-critical-unauthenticated-remote-system-configuration-vulnerability-in-voltronic-power-viewpower-powershield-netguard\/\"  data-wpil-monitor-id=\"83171\">vulnerability arises from OAuth2-Proxy&#8217;s use of the skip_auth_routes configuration<\/a> option with regex patterns. Attackers can craft URLs with query parameters that satisfy the configured regex patterns, thereby <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-7692-authentication-bypass-vulnerability-in-orion-login-with-sms-plugin-for-wordpress\/\"  data-wpil-monitor-id=\"69954\">bypassing authentication<\/a>. The issue is primarily due to skip_auth_routes matching against the full request URI, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-50105-critical-vulnerability-in-oracle-universal-work-queue-allowing-unauthorized-data-access\/\"  data-wpil-monitor-id=\"69957\">allowing unauthorized<\/a> access if the configured regex patterns are overly permissive, contain wildcards, or broad matching patterns.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-2009333232\" 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>Suppose there&#8217;s a misconfigured regex pattern in the skip_auth_routes that allows anything ending with a &#8220;\/public&#8221;. An <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-42959-unauthenticated-replay-attack-exploiting-hmac-reuse\/\"  data-wpil-monitor-id=\"75858\">attacker could exploit<\/a> this by crafting a URL with query parameters like so:<\/p>\n<pre><code class=\"\" data-line=\"\">GET \/private?redirect=\/public HTTP\/1.1\nHost: vulnerable.example.com<\/code><\/pre>\n<p>This would <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-45777-critical-vulnerability-in-otp-mechanism-bypassing-authentication-in-chavara-matrimony-site\/\"  data-wpil-monitor-id=\"70922\">bypass the authentication<\/a> due to the misconfigured regex pattern, giving the attacker unauthorized access to the private endpoint.<\/p>\n<p><strong>Mitigation and Workarounds<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-46198-cross-site-scripting-vulnerability-in-grav-versions-1-7-46-to-1-7-48\/\"  data-wpil-monitor-id=\"69955\">vulnerability is fixed in OAuth2-Proxy version<\/a> 7.11.0. It is highly recommended to update to this version or later to mitigate this issue. If immediate patching is not possible, consider implementing workarounds such as:<br \/>\n&#8211; Auditing all skip_auth_routes configurations for overly permissive patterns.<br \/>\n&#8211; Replacing wildcard patterns with exact path matches where possible.<br \/>\n&#8211; Ensuring regex patterns are properly anchored (starting with ^ and ending with $).<br \/>\n&#8211; Implementing custom validation that strips query parameters before regex matching.<br \/>\n&#8211; Utilize Web Application Firewall (WAF) or Intrusion Detection System (IDS) for temporary mitigation.<br \/>\nAlways ensure to follow best practices for security configuration and regularly update your <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-33077-local-stack-based-buffer-overflow-vulnerability-in-ibm-engineering-systems-design-rhapsody\/\"  data-wpil-monitor-id=\"69958\">systems to the latest versions to prevent similar vulnerabilities<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview OAuth2-Proxy, an open-source reverse proxy middleware, is suffering from a critical vulnerability affecting versions 7.10.0 and below. This vulnerability can enable attackers to bypass authentication using the skip_auth_routes configuration option with regex patterns. Consequently, unauthorized users can gain access to protected resources, leading to potential system compromise and data leakage. The issue is of [&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":[75],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-59912","post","type-post","status-publish","format-standard","hentry","category-uncategorized","attack_vector-authentication-bypass"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59912","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=59912"}],"version-history":[{"count":5,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59912\/revisions"}],"predecessor-version":[{"id":75708,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59912\/revisions\/75708"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=59912"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=59912"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=59912"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=59912"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=59912"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=59912"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=59912"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=59912"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=59912"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}