{"id":"USN-4434-1","summary":"libvncserver vulnerabilities","details":"Ramin Farajpour Cami discovered that LibVNCServer incorrectly handled\ncertain malformed unix socket names. A remote attacker could exploit this\nwith a crafted socket name, leading to a denial of service, or possibly\nexecute arbitrary code. (CVE-2019-20839)\n\nIt was discovered that LibVNCServer did not properly access byte-aligned\ndata. A remote attacker could possibly use this issue to cause\nLibVNCServer to crash, resulting in a denial of service. This issue only\naffected Ubuntu 18.04 LTS and Ubuntu 16.04 LTS. (CVE-2019-20840)\n\nChristian Beier discovered that LibVNCServer incorrectly handled anonymous\nTLS connections. A remote attacker could possibly use this issue to cause\nLibVNCServer to crash, resulting in a denial of service. This issue only\naffected Ubuntu 20.04 LTS. (CVE-2020-14396)\n\nIt was discovered that LibVNCServer incorrectly handled region clipping. A\nremote attacker could possibly use this issue to cause LibVNCServer to\ncrash, resulting in a denial of service. (CVE-2020-14397)\n\nIt was discovered that LibVNCServer did not properly reset incorrectly\nterminated TCP connections. A remote attacker could possibly use this\nissue to cause an infinite loop, resulting in a denial of service.\n(CVE-2020-14398)\n\nIt was discovered that LibVNCServer did not properly access byte-aligned\ndata. A remote attacker could possibly use this issue to cause\nLibVNCServer to crash, resulting in a denial of service. (CVE-2020-14399,\nCVE-2020-14400)\n\nIt was discovered that LibVNCServer incorrectly handled screen scaling on\nthe server side. A remote attacker could use this issue to cause\nLibVNCServer to crash, resulting in a denial of service, or possibly\nexecute arbitrary code. (CVE-2020-14401)\n\nIt was discovered that LibVNCServer incorrectly handled encodings. A\nremote attacker could use this issue to cause LibVNCServer to crash,\nresulting in a denial of service, or possibly execute arbitrary code.\n(CVE-2020-14402, CVE-2020-14403, CVE-2020-14404)\n\nIt was discovered that LibVNCServer incorrectly handled TextChat messages.\nA remote attacker could possibly use this issue to cause LibVNCServer to\ncrash, resulting in a denial of service. (CVE-2020-14405)\n","modified":"2026-04-27T15:48:20.666970225Z","published":"2020-07-23T20:09:25Z","related":["UBUNTU-CVE-2019-20839","UBUNTU-CVE-2019-20840","UBUNTU-CVE-2020-14396","UBUNTU-CVE-2020-14397","UBUNTU-CVE-2020-14398","UBUNTU-CVE-2020-14399","UBUNTU-CVE-2020-14400","UBUNTU-CVE-2020-14401","UBUNTU-CVE-2020-14402","UBUNTU-CVE-2020-14403","UBUNTU-CVE-2020-14404","UBUNTU-CVE-2020-14405"],"upstream":["CVE-2019-20839","CVE-2019-20840","CVE-2020-14396","CVE-2020-14397","CVE-2020-14398","CVE-2020-14399","CVE-2020-14400","CVE-2020-14401","CVE-2020-14402","CVE-2020-14403","CVE-2020-14404","CVE-2020-14405","UBUNTU-CVE-2019-20839","UBUNTU-CVE-2019-20840","UBUNTU-CVE-2020-14396","UBUNTU-CVE-2020-14397","UBUNTU-CVE-2020-14398","UBUNTU-CVE-2020-14399","UBUNTU-CVE-2020-14400","UBUNTU-CVE-2020-14401","UBUNTU-CVE-2020-14402","UBUNTU-CVE-2020-14403","UBUNTU-CVE-2020-14404","UBUNTU-CVE-2020-14405"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4434-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2019-20839"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2019-20840"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14396"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14397"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14398"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14399"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14400"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14401"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14402"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14403"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14404"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-14405"}],"affected":[{"package":{"name":"libvncserver","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/libvncserver@0.9.10+dfsg-3ubuntu0.16.04.5?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.10+dfsg-3ubuntu0.16.04.5"}]}],"versions":["0.9.10+dfsg-3","0.9.10+dfsg-3build1","0.9.10+dfsg-3ubuntu0.16.04.1","0.9.10+dfsg-3ubuntu0.16.04.2","0.9.10+dfsg-3ubuntu0.16.04.3","0.9.10+dfsg-3ubuntu0.16.04.4"],"ecosystem_specific":{"binaries":[{"binary_name":"libvncclient1","binary_version":"0.9.10+dfsg-3ubuntu0.16.04.5"},{"binary_name":"libvncserver-config","binary_version":"0.9.10+dfsg-3ubuntu0.16.04.5"},{"binary_name":"libvncserver1","binary_version":"0.9.10+dfsg-3ubuntu0.16.04.5"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4434-1.json","cves_map":{"ecosystem":"Ubuntu:16.04:LTS","cves":[{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2019-20839"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2019-20840"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14397"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14398"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14399"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14400"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14401"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14402"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14403"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14404"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2020-14405"}]}}},{"package":{"name":"libvncserver","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libvncserver@0.9.11+dfsg-1ubuntu1.3?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.11+dfsg-1ubuntu1.3"}]}],"versions":["0.9.11+dfsg-1","0.9.11+dfsg-1ubuntu1","0.9.11+dfsg-1ubuntu1.1","0.9.11+dfsg-1ubuntu1.2"],"ecosystem_specific":{"binaries":[{"binary_name":"libvncclient1","binary_version":"0.9.11+dfsg-1ubuntu1.3"},{"binary_name":"libvncserver-config","binary_version":"0.9.11+dfsg-1ubuntu1.3"},{"binary_name":"libvncserver1","binary_version":"0.9.11+dfsg-1ubuntu1.3"}],"availability":"No 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