{"id":"CVE-2019-20840","details":"An issue was discovered in LibVNCServer before 0.9.13. libvncserver/ws_decode.c can lead to a crash because of unaligned accesses in hybiReadAndDecode.","modified":"2026-08-07T15:18:59.363496Z","published":"2020-06-17T16:15:11.523Z","related":["SUSE-SU-2020:1922-1","SUSE-SU-2020:2167-1","openSUSE-SU-2020:0988-1","openSUSE-SU-2020:1025-1","openSUSE-SU-2020:1056-1","openSUSE-SU-2024:10598-1"],"database_specific":{"unresolved_ranges":[{"cpes":["cpe:2.3:o:siemens:simatic_itc1500_firmware:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.0.0.0"},{"fixed":"3.2.1.0"}],"source":"CPE_RANGE","vendor_product":"siemens:simatic_itc1500_firmware"},{"cpes":["cpe:2.3:o:siemens:simatic_itc1500_pro_firmware:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.0.0.0"},{"fixed":"3.2.1.0"}],"source":"CPE_RANGE","vendor_product":"siemens:simatic_itc1500_pro_firmware"},{"cpes":["cpe:2.3:o:siemens:simatic_itc1900_firmware:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.0.0.0"},{"fixed":"3.2.1.0"}],"source":"CPE_RANGE","vendor_product":"siemens:simatic_itc1900_firmware"},{"vendor_product":"siemens:simatic_itc1900_pro_firmware","cpes":["cpe:2.3:o:siemens:simatic_itc1900_pro_firmware:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.0.0.0"},{"fixed":"3.2.1.0"}],"source":"CPE_RANGE"},{"cpes":["cpe:2.3:o:siemens:simatic_itc2200_firmware:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.0.0.0"},{"fixed":"3.2.1.0"}],"source":"CPE_RANGE","vendor_product":"siemens:simatic_itc2200_firmware"},{"cpes":["cpe:2.3:o:siemens:simatic_itc2200_pro_firmware:*:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"3.0.0.0"},{"fixed":"3.2.1.0"}],"source":"CPE_RANGE","vendor_product":"siemens:simatic_itc2200_pro_firmware"},{"cpes":["cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*","cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*"],"extracted_events":[{"introduced":"14.04"},{"last_affected":"14.04"},{"introduced":"16.04"},{"last_affected":"16.04"},{"introduced":"16.04"},{"last_affected":"16.04"},{"introduced":"18.04"},{"last_affected":"18.04"},{"introduced":"18.10"},{"last_affected":"18.10"},{"introduced":"20.04"},{"last_affected":"20.04"}],"source":"CPE_STRING","vendor_product":"canonical:ubuntu_linux"},{"cpes":["cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*","cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"8.0"},{"last_affected":"8.0"},{"introduced":"9.0"},{"last_affected":"9.0"}],"source":"CPE_STRING","vendor_product":"debian:debian_linux"},{"cpes":["cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*"],"extracted_events":[{"introduced":"15.2"},{"last_affected":"15.2"}],"source":"CPE_STRING","vendor_product":"opensuse:leap"}]},"references":[{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4F6FUH4EFK4NAP6GT4TQRTBKWIRCZLIY/"},{"type":"ADVISORY","url":"http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00033.html"},{"type":"ADVISORY","url":"http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00055.html"},{"type":"ADVISORY","url":"http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00066.html"},{"type":"ADVISORY","url":"https://github.com/LibVNC/libvncserver/compare/LibVNCServer-0.9.12...LibVNCServer-0.9.13"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/4434-1/"},{"type":"FIX","url":"https://cert-portal.siemens.com/productcert/pdf/ssa-390195.pdf"},{"type":"FIX","url":"https://github.com/LibVNC/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/libvnc/libvncserver","events":[{"introduced":"0"},{"last_affected":"0a70095271d845d16a3ed17354841b01f33963ad"},{"fixed":"0cf1400c61850065de590d403f6d49e32882fd76"}],"database_specific":{"cpe":"cpe:2.3:a:libvnc_project:libvncserver:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"last_affected":"0.9.12"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["LibVNCServer-0.9.12","LibVNCServer-0.9.11","LibVNCServer-0.9.10","LibVNCServer-0.9.9","LibVNCServer-0.9.8","X11VNC_0_9_12","X11VNC_0_9_11","X11VNC_0_9_10","X11VNC_0_9_9","X11VNC_0_9_8","X11VNC_0_9_7","X11VNC_REL_0_9_6","X11VNC_REL_0_9_5","X11VNC_REL_0_9_4"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2019-20840.json","vanir_signatures_modified":"2026-08-07T15:18:59Z","vanir_signatures":[{"digest":{"function_hash":"180079713415210745791807162750284308920","length":4063},"id":"CVE-2019-20840-10709c66","signature_type":"Function","signature_version":"v1","source":"https://github.com/libvnc/libvncserver/commit/0cf1400c61850065de590d403f6d49e32882fd76","target":{"file":"libvncserver/ws_decode.c","function":"hybiReadAndDecode"},"deprecated":false},{"deprecated":false,"digest":{"line_hashes":["280535027786460026972189112772063445853","50701751959996758734036103654922009095",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