{"id":35427,"date":"2025-05-06T11:22:27","date_gmt":"2025-05-06T11:22:27","guid":{"rendered":""},"modified":"2025-06-17T05:19:20","modified_gmt":"2025-06-17T11:19:20","slug":"cve-2023-35994-critical-array-index-validation-vulnerabilities-in-gtkwave","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2023-35994-critical-array-index-validation-vulnerabilities-in-gtkwave\/","title":{"rendered":"<strong>CVE-2023-35994: Critical Array Index Validation Vulnerabilities in GTKWave<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>This article discusses a critical vulnerability identified as CVE-2023-35994 that exists in the popular open-source waveform viewer, GTKWave. This vulnerability specifically affects the &#8216;fstReaderIterBlocks2 tdelta&#8217; functionality of GTKWave version 3.3.115. Cybersecurity researchers have found that it can be exploited via a carefully crafted .fst <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-3065-arbitrary-file-deletion-vulnerability-in-database-toolset-plugin\/\"  data-wpil-monitor-id=\"40234\">file leading to arbitrary<\/a> code execution. The severity of this vulnerability stems from the fact that it can <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-3914-potential-arbitrary-file-uploads-and-system-compromise-in-aeropage-sync-for-airtable-wordpress-plugin\/\"  data-wpil-monitor-id=\"40598\">potentially lead to system compromise<\/a> or data leakage, posing a significant risk to users and organizations using the affected software version.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2023-35994<br \/>\nSeverity: High (7.8 CVSS)<br \/>\nAttack Vector: Opening a malicious .fst file<br \/>\nPrivileges Required: None<br \/>\nUser Interaction: Required<br \/>\nImpact: System compromise and <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2023-50612-escalation-of-privileges-and-data-leakage-in-fit2cloud-cloud-explorer-lite\/\"  data-wpil-monitor-id=\"41280\">data leakage<\/a><\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-2280334067\" 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>GTKWave | 3.3.115<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>This exploit takes advantage of improper array index validation <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2023-34436-critical-out-of-bounds-write-vulnerability-in-gtkwave-3-3-115\/\"  data-wpil-monitor-id=\"41041\">vulnerabilities in the &#8216;fstReaderIterBlocks2 tdelta&#8217; functionality of GTKWave<\/a>. An attacker <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-24189-memory-corruption-vulnerability-due-to-maliciously-crafted-web-content-in-various-operating-systems\/\"  data-wpil-monitor-id=\"59174\">crafts a malicious<\/a> .fst file and sends it to the victim. Once the victim opens this file using GTKWave, the software fails to properly validate the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2023-34087-code-execution-vulnerability-in-gtkwave-3-3-115-through-improper-array-index-validation\/\"  data-wpil-monitor-id=\"41533\">array indexes<\/a> within the file. This failure allows the attacker to execute code arbitrarily on the victim&#8217;s system, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-22636-cross-site-scripting-vulnerability-in-vr-frases-leads-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"40171\">potentially leading to system<\/a> compromise or data leakage.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-3157484792\" 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>Although the exact nature of the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-3200-unauthenticated-remote-attacker-exploiting-insecure-tls-protocols\/\"  data-wpil-monitor-id=\"40784\">exploit code will vary based on the attacker&#8217;s<\/a> intent, a conceptual example might look like this:<\/p>\n<pre><code class=\"\" data-line=\"\">block\n{\ntype: tdelta\nindex: 99999999999\npayload: {\n&quot;executable_code&quot;: &quot;malicious code here&quot;\n}\n}<\/code><\/pre>\n<p>In this example, the &#8220;index&#8221; value is higher than what the application can handle, and the &#8220;executable_code&#8221; contains the attacker&#8217;s malicious <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-43946-critical-remote-code-execution-vulnerability-in-tcpwave-ddi\/\"  data-wpil-monitor-id=\"40332\">code to be executed<\/a> on the target system.<\/p>\n<p><strong>Mitigation Guidance<\/strong><\/p>\n<p>To mitigate this vulnerability, users are advised to apply the vendor patch as soon as it becomes available. Until then, users can use a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as a temporary mitigation measure. These systems can help detect and <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2023-35989-integer-overflow-vulnerability-in-gtkwave-s-lxt2-zlib-block-allocation\/\"  data-wpil-monitor-id=\"41963\">block attempts to exploit this vulnerability<\/a>. Also, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-3055-critical-arbitrary-file-deletion-vulnerability-in-wp-user-frontend-pro-plugin\/\"  data-wpil-monitor-id=\"59173\">users should be cautious while opening .fst files<\/a> from unknown sources.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview This article discusses a critical vulnerability identified as CVE-2023-35994 that exists in the popular open-source waveform viewer, GTKWave. This vulnerability specifically affects the &#8216;fstReaderIterBlocks2 tdelta&#8217; functionality of GTKWave version 3.3.115. Cybersecurity researchers have found that it can be exploited via a carefully crafted .fst file leading to arbitrary code execution. The severity of this [&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":[80],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-35427","post","type-post","status-publish","format-standard","hentry","category-uncategorized","attack_vector-rce"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/35427","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=35427"}],"version-history":[{"count":10,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/35427\/revisions"}],"predecessor-version":[{"id":52882,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/35427\/revisions\/52882"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=35427"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=35427"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=35427"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=35427"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=35427"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=35427"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=35427"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=35427"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=35427"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}