{"id":"ALSA-2021:1811","summary":"Moderate: libvncserver security update","details":"LibVNCServer is a C library that enables you to implement VNC server functionality into own programs.\n\nSecurity Fix(es):\n\n* libvncserver: uninitialized memory contents are vulnerable to Information Leak (CVE-2018-21247)\n\n* libvncserver: buffer overflow in ConnectClientToUnixSock() (CVE-2019-20839)\n\n* libvncserver: libvncserver/rfbregion.c has a NULL pointer dereference (CVE-2020-14397)\n\n* libvncserver: libvncclient/rfbproto.c does not limit TextChat size (CVE-2020-14405)\n\n* libvncserver: libvncserver/rfbserver.c has a divide by zero which could result in DoS (CVE-2020-25708)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n\nAdditional Changes:\n\nFor detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.","modified":"2026-01-30T01:50:34.089177Z","published":"2021-05-18T06:09:01Z","related":["CVE-2018-21247","CVE-2019-20839","CVE-2020-14397","CVE-2020-14405","CVE-2020-25708"],"references":[{"type":"ADVISORY","url":"https://errata.almalinux.org/8/ALSA-2021-1811.html"},{"type":"REPORT","url":"https://vulners.com/cve/CVE-2018-21247"},{"type":"REPORT","url":"https://vulners.com/cve/CVE-2019-20839"},{"type":"REPORT","url":"https://vulners.com/cve/CVE-2020-14397"},{"type":"REPORT","url":"https://vulners.com/cve/CVE-2020-14405"},{"type":"REPORT","url":"https://vulners.com/cve/CVE-2020-25708"}],"affected":[{"package":{"name":"libvncserver","ecosystem":"AlmaLinux:8","purl":"pkg:rpm/almalinux/libvncserver"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.11-17.el8"}]}],"database_specific":{"source":"https://github.com/AlmaLinux/osv-database/blob/master/advisories/almalinux8/ALSA-2021:1811.json"}},{"package":{"name":"libvncserver-devel","ecosystem":"AlmaLinux:8","purl":"pkg:rpm/almalinux/libvncserver-devel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.11-17.el8"}]}],"database_specific":{"source":"https://github.com/AlmaLinux/osv-database/blob/master/advisories/almalinux8/ALSA-2021:1811.json"}}],"schema_version":"1.7.3"}