{"id":69781,"date":"2025-09-01T02:15:30","date_gmt":"2025-09-01T02:15:30","guid":{"rendered":""},"modified":"2025-09-03T14:30:21","modified_gmt":"2025-09-03T20:30:21","slug":"cve-2025-51606-critical-security-vulnerability-in-hippo4j-due-to-hard-coded-jwt-secret-key","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-51606-critical-security-vulnerability-in-hippo4j-due-to-hard-coded-jwt-secret-key\/","title":{"rendered":"<strong>CVE-2025-51606: Critical Security Vulnerability in hippo4j Due to Hard-Coded JWT Secret Key<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The Common Vulnerabilities and Exposures (CVE) system has recently identified a critical security vulnerability, designated as CVE-2025-51606, affecting versions 1.0.0 to 1.5.0 of the hippo4j software. This vulnerability, which pertains to the use of a hard-coded secret key in JWT (JSON Web Token) creation, poses a significant security risk to any systems where authentication and authorization rely heavily on the integrity of JWTs. If exploited, it could <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-42950-sap-landscape-transformation-vulnerability-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"77561\">lead to system<\/a> compromise or data leakage and, therefore, it is of paramount importance that users take immediate steps to mitigate the threat.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-51606<br \/>\nSeverity: High (Score: 8.8)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-8939-buffer-overflow-vulnerability-in-tenda-ac20-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"78296\">Potential system<\/a> compromise or data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-1792342900\" 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>hippo4j | 1.0.0 to 1.5.0<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-8730-critical-vulnerability-in-belkin-routers-due-to-hard-coded-credentials\/\"  data-wpil-monitor-id=\"81067\">vulnerability arises from the use of a hard-coded<\/a> secret key for JWT creation in hippo4j. An attacker with access to the source <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-21165-out-of-bounds-write-vulnerability-in-substance3d-designer-leading-to-arbitrary-code-execution\/\"  data-wpil-monitor-id=\"77465\">code or compiled binary can exploit this vulnerability<\/a> by forging valid access tokens and impersonating any user, even privileged ones such as &#8220;admin. This allows the attacker to <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2024-57491-authentication-bypass-vulnerability-in-jobx-up-to-v1-0-1\/\"  data-wpil-monitor-id=\"77624\">bypass authentication<\/a> measures and gain unauthorized access to the system.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-4182253046\" 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>Here\u2019s a conceptual example of how the vulnerability might be exploited. This is a pseudocode for creating a forged JWT:<\/p>\n<pre><code class=\"\" data-line=\"\"># Import JWT library\nimport jwt\n# Define hard-coded secret key\nsecret_key = &quot;hard-coded-secret-key-from-hippo4j&quot;\n# Define malicious payload with admin privileges\nmalicious_payload = {\n&quot;user&quot;: &quot;admin&quot;,\n&quot;privileges&quot;: &quot;all&quot;\n}\n# Forge JWT using the secret key and malicious payload\nforged_token = jwt.encode(malicious_payload, secret_key, algorithm=&#039;HS256&#039;)\n# Now the attacker can use this forged_token to impersonate as admin<\/code><\/pre>\n<p>Keep in mind that this is a hypothetical example and the actual code or method used by an attacker may vary based on the specific circumstances and the attacker&#8217;s knowledge and resources. Nonetheless, it demonstrates the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47107-heap-based-buffer-overflow-vulnerability-in-incopy-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"78350\">potential severity and exploitability of the vulnerability<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The Common Vulnerabilities and Exposures (CVE) system has recently identified a critical security vulnerability, designated as CVE-2025-51606, affecting versions 1.0.0 to 1.5.0 of the hippo4j software. This vulnerability, which pertains to the use of a hard-coded secret key in JWT (JSON Web Token) creation, poses a significant security risk to any systems where authentication [&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-69781","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\/69781","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=69781"}],"version-history":[{"count":6,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/69781\/revisions"}],"predecessor-version":[{"id":73513,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/69781\/revisions\/73513"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=69781"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=69781"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=69781"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=69781"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=69781"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=69781"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=69781"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=69781"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=69781"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}