{"id":55255,"date":"2025-06-26T21:05:51","date_gmt":"2025-06-26T21:05:51","guid":{"rendered":""},"modified":"2025-09-02T21:31:44","modified_gmt":"2025-09-03T03:31:44","slug":"cve-2025-35940-hard-coded-jwt-signing-key-vulnerability-in-archiverspaapi-asp-net-application","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-35940-hard-coded-jwt-signing-key-vulnerability-in-archiverspaapi-asp-net-application\/","title":{"rendered":"<strong>CVE-2025-35940: Hard-coded JWT Signing Key Vulnerability in ArchiverSpaApi ASP.NET Application<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The vulnerability designated as CVE-2025-35940 is a critical flaw discovered in the ArchiverSpaApi ASP.NET application. This application&#8217;s <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-28389-critical-security-vulnerability-in-openc3-cosmos-v6-0-0-due-to-weak-password-requirements\/\"  data-wpil-monitor-id=\"61602\">security vulnerability<\/a> arises from the use of a hard-coded JSON Web Token (JWT) signing key. The flaw potentially affects all entities that utilize the affected application, and could <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47167-microsoft-office-type-confusion-vulnerability-leading-to-unauthorized-local-code-execution\/\"  data-wpil-monitor-id=\"61767\">lead to unauthorized<\/a> access, system compromise, or data leakage. The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-6172-high-severity-permission-vulnerability-in-mobile-applications\/\"  data-wpil-monitor-id=\"61730\">severity of this vulnerability<\/a> highlights the importance of robust cybersecurity practices, especially in the area of access control and authentication management.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-35940<br \/>\nSeverity: High (CVSS: 8.1)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: None<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49181-unauthorized-api-endpoint-access-leading-to-denial-of-service-and-data-leakage\/\"  data-wpil-monitor-id=\"61687\">Unauthorized access to protected API endpoints<\/a>, potential system compromise and data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-3086983724\" 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>ArchiverSpaApi ASP.NET Application | All <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49137-critical-vulnerability-in-hax-cms-php-prior-to-version-11-0-0\/\"  data-wpil-monitor-id=\"61967\">versions prior<\/a> to the patch<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The CVE-2025-35940 <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-36038-remote-code-execution-vulnerability-in-ibm-websphere-application-server\/\"  data-wpil-monitor-id=\"64690\">vulnerability stems from the application&#8217;s<\/a> use of a hard-coded JWT signing key. This key is used to verify the integrity of JWT tokens, which are often used for user authentication and <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49154-insecure-access-control-vulnerability-in-trend-micro-products\/\"  data-wpil-monitor-id=\"62730\">access control<\/a>. An attacker with knowledge of this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49151-unauthenticated-attackers-can-forge-json-web-tokens-in-microsens-nmp-web\/\"  data-wpil-monitor-id=\"64547\">key can generate and sign their own JWT<\/a> tokens. These tokens would be accepted as valid by the application, granting the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-25268-unauthenticated-adjacent-attacker-accessing-api-endpoint\/\"  data-wpil-monitor-id=\"77742\">attacker access<\/a> to protected API endpoints.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-3979219354\" 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>An attacker might exploit this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47164-code-execution-vulnerability-in-microsoft-office-via-use-after-free-error\/\"  data-wpil-monitor-id=\"61849\">vulnerability via<\/a> a HTTP request like the one below. In this example, the attacker crafts a malicious JWT token (&#8220;eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9&#8230;&#8221;) using the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-26476-unauthorized-access-by-use-of-hard-coded-cryptographic-key-in-dell-ecs-and-objectscale\/\"  data-wpil-monitor-id=\"74060\">hard-coded signing key<\/a> and includes it in the Authorization header:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/protected\/endpoint HTTP\/1.1\nHost: target.example.com\nContent-Type: application\/json\nAuthorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...\n{ &quot;malicious_payload&quot;: &quot;...&quot; }<\/code><\/pre>\n<p>This request would be accepted by the server as if it were from an authenticated user, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-25264-critical-vulnerability-allowing-unauthenticated-remote-access-due-to-overly-permissive-cors-policy\/\"  data-wpil-monitor-id=\"61923\">allowing the attacker to perform actions or access<\/a> data they should not be able to.<\/p>\n<p><strong>Guidance on Mitigation and Patching<\/strong><\/p>\n<p>The recommended <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-39486-rankie-sql-injection-vulnerability-and-mitigation-measures\/\"  data-wpil-monitor-id=\"62731\">mitigation for this vulnerability<\/a> is to apply the vendor-supplied patch, which replaces the hard-coded signing key with a secure, randomly generated one. If the patch cannot be applied immediately, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used as a temporary mitigation measure. These <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52890-critical-acl-bypass-vulnerability-in-incus-system-container-and-virtual-machine-manager\/\"  data-wpil-monitor-id=\"64741\">systems can be configured to block requests containing<\/a> known malicious JWT tokens. However, this is a stop-gap measure and not a full solution; the vendor&#8217;s patch should be applied as soon as possible.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The vulnerability designated as CVE-2025-35940 is a critical flaw discovered in the ArchiverSpaApi ASP.NET application. This application&#8217;s security vulnerability arises from the use of a hard-coded JSON Web Token (JWT) signing key. The flaw potentially affects all entities that utilize the affected application, and could lead to unauthorized access, system compromise, or 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-55255","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\/55255","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=55255"}],"version-history":[{"count":13,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/55255\/revisions"}],"predecessor-version":[{"id":70141,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/55255\/revisions\/70141"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=55255"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=55255"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=55255"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=55255"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=55255"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=55255"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=55255"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=55255"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=55255"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}