{"schemaVersion":3,"id":"CVE-2023-43826","aliases":["UBUNTU-CVE-2023-43826"],"status":"published","duplicateOf":null,"title":null,"description":"Apache Guacamole 1.5.3 and older do not consistently ensure that values received from a VNC server will not result in integer overflow. If a user connects to a malicious or compromised VNC server, specially-crafted data could result in memory corruption, possibly allowing arbitrary code to be executed with the privileges of the running guacd process.\n\nUsers are recommended to upgrade to version 1.5.4, which fixes this issue.","dates":{"published":"2023-12-19T19:50:15.188Z","modified":"2026-02-25T17:51:44.807Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":8.8,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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This occurs when an integer value is\n         incremented to a value that is too large to store in the\n         associated representation. When this occurs, the value may\n         become a very small or negative number.","type":"weakness","status":"Stable","abstraction":"Base","likelihoodOfExploit":"Medium","url":"https://cwe.mitre.org/data/definitions/190.html"}],"affected":[{"vendor":"apache software foundation","product":"apache guacamole","name":"Apache Guacamole","label":"apache guacamole","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≤ 1.5.3","noFixRecorded":false,"fixedIn":null}],"versionsText":"≤ 1.5.3","eol":null,"hubHref":"/vendor/apache_software_foundation/apache_guacamole"},{"vendor":"apache","product":"guacamole","name":"guacamole","label":"guacamole","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≤ 1.5.3","noFixRecorded":false,"fixedIn":null}],"versionsText":"≤ 1.5.3","eol":null,"hubHref":"/vendor/apache/guacamole"},{"vendor":"ubuntu","product":"guacamole-client","name":"guacamole-client","label":"guacamole-client","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/guacamole-client","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://lists.apache.org/thread/23gzwftpfgtq97tj6ttmbclry53kmwv6","label":"lists.apache.org/thread/23gzwftpfgtq97tj6ttmbclry53kmwv6","hostname":"lists.apache.org","tags":["Vendor Advisory","REPORT","Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2023/12/19/4","label":"www.openwall.com/lists/oss-security/2023/12/19/4","hostname":"www.openwall.com","tags":["REPORT","Mailing List","Third Party Advisory"]},{"url":"https://ubuntu.com/security/CVE-2023-43826","label":"ubuntu.com/security/CVE-2023-43826","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-43826","label":"www.cve.org/CVERecord?id=CVE-2023-43826","hostname":"www.cve.org","tags":["REPORT"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2023-12-19T19:50:15.188Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-02-25T17:51:44.807Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":35,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T08:20:07.543Z","stale":false,"partial":false}}