{"id":"CVE-2020-14396","aliases":["DEBIAN-CVE-2020-14396","EUVD-2020-6535","GHSA-f7mr-g388-r763","UBUNTU-CVE-2020-14396","USN-4434-1"],"status":"published","title":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL...","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.02637,"percentile":0.85761,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-476"],"published":"2020-06-17T15:13:40Z","modified":"2026-10-26T12:01:37Z","fixes":[{"ecosystem":"Debian:12","package":"libvncserver","fixed_in":["0.9.13+dfsg-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"libvncserver","fixed_in":["0.9.13+dfsg-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"libvncserver","fixed_in":["0.9.13+dfsg-1"],"sources":["osv"]},{"ecosystem":"Ubuntu:20.04:LTS","package":"libvncserver","fixed_in":["0.9.12+dfsg-9ubuntu0.2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"libvncserver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.13+dfsg-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"libvncserver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.13+dfsg-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"libvncserver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.13+dfsg-1"}]}]},{"source":"osv","ecosystem":"Ubuntu:14.04:LTS","package":"x11vnc","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.9.13-1.1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"libvncserver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.12+dfsg-9ubuntu0.2"}]}],"versions":["0.9.11+dfsg-1.3","0.9.12+dfsg-3ubuntu3","0.9.12+dfsg-6","0.9.12+dfsg-7","0.9.12+dfsg-8","0.9.12+dfsg-9","0.9.12+dfsg-9ubuntu0.1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"veyon","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.4+repack1-2","4.2.5+repack1-1","4.3.1+repack1-1","4.3.1+repack1-2","4.3.1+repack1-2build1","4.3.1+repack1-2build2"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"veyon","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.5.3+repack1-1build1","4.5.3+repack1-1build2"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"veyon","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.7.5+repack1-1build2","4.7.5+repack1-1ubuntu1","4.7.5+repack1-1ubuntu3","4.7.5+repack1-1ubuntu4","4.7.5+repack1-1ubuntu5"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"veyon","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.7.5+repack1-1ubuntu6","4.7.5+repack1-1ubuntu7","4.9.7+repack1-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"veyon","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.9.7+repack1-1build1","4.9.7+repack1-1.1","4.9.7+repack1-1.1build1","4.9.7+repack1-1.1build2"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"veyon","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.9.7+repack1-1","4.9.7+repack1-1build1"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"libvncserver","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"],"bundled":12},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"libvncserver","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"],"bundled":12},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"libvncserver","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.12+dfsg-9ubuntu0.2"}]}],"versions":["0.9.11+dfsg-1.3","0.9.12+dfsg-3ubuntu3","0.9.12+dfsg-6","0.9.12+dfsg-7","0.9.12+dfsg-8","0.9.12+dfsg-9","0.9.12+dfsg-9ubuntu0.1"],"bundled":12}],"products":[{"vendor":"canonical","product":"ubuntu_linux"},{"vendor":"debian","product":"debian_linux"},{"vendor":"libvnc_project","product":"libvncserver"},{"vendor":"siemens","product":"simatic_itc1500_firmware"},{"vendor":"siemens","product":"simatic_itc1500_pro_firmware"},{"vendor":"siemens","product":"simatic_itc1900_firmware"},{"vendor":"siemens","product":"simatic_itc1900_pro_firmware"},{"vendor":"siemens","product":"simatic_itc2200_firmware"},{"vendor":"siemens","product":"simatic_itc2200_pro_firmware"}],"references":[{"url":"https://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13","tags":["x_refsource_MISC","x_transferred","Release Notes","Third Party Advisory","advisory","report"]},{"url":"https://github.com/LibVNC/libvncserver/commit/33441d90a506d5f3ae9388f2752901227e430553","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","report"]},{"url":"https://usn.ubuntu.com/4434-1/","tags":["vendor-advisory","x_refsource_UBUNTU","x_transferred","Third Party Advisory","advisory"]},{"url":"https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf","tags":["x_refsource_CONFIRM","x_transferred","Patch","Third Party Advisory","fix"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-14396"},{"url":"https://github.com/advisories/GHSA-f7mr-g388-r763"},{"url":"https://security-tracker.debian.org/tracker/CVE-2020-14396","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2020-14396","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-4434-1","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2020-14396","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-20839","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-20840","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14397","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14398","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14399","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14400","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14401","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14402","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14403","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14404","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2020-14405","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2020-14396","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2020-06-17T15:13:40Z","modified":"2024-08-04T12:46:34.415Z","updated_at":"2026-11-02T14:35:46.873079Z"}],"euvd":[{"id":"EUVD-2020-6535","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2020-06-17T15:13:40Z","modified":"2024-08-04T12:46:34Z","updated_at":"2026-11-03T03:07:34.099541Z"}],"ghsa":[{"id":"GHSA-f7mr-g388-r763","title":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL...","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2022-05-24T17:20:47Z","modified":"2023-01-29T05:03:20Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:45:17.6265Z"}],"nvd":[{"id":"CVE-2020-14396","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2020-06-17T16:15:11.697Z","modified":"2026-06-17T02:54:41.503Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-476"],"updated_at":"2026-11-02T14:06:07.249892Z"}],"osv":[{"id":"CVE-2020-14396","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2020-06-17T16:15:11.697Z","modified":"2026-10-20T13:50:31.22210969Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:14.418339Z"},{"id":"DEBIAN-CVE-2020-14396","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2020-06-17T16:15:11.697Z","modified":"2026-10-26T12:01:37.286000383Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:33.384087Z"},{"id":"UBUNTU-CVE-2020-14396","description":"An issue was discovered in LibVNCServer before 0.9.13. libvncclient/tls_openssl.c has a NULL pointer dereference.","status":"published","published":"2020-06-17T16:15:00Z","modified":"2026-10-17T12:55:44.113341183Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:22.804634Z"},{"id":"USN-4434-1","title":"libvncserver vulnerabilities","description":"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","status":"published","published":"2020-07-23T20:09:25Z","modified":"2026-04-27T15:48:46.367539073Z","updated_at":"2026-11-02T16:58:14.547547Z"}]}}