{"id":"USN-8494-1","summary":"libvncserver vulnerability","details":"It was discovered that LibVNCServer incorrectly handled the Tight decoder\nin libvncclient. A remote attacker could use this issue to cause\nLibVNCServer to crash, resulting in a denial of service, or possibly\nexecute arbitrary code.","modified":"2026-08-24T10:54:34.409349831Z","published":"2026-07-02T13:22:47Z","related":["UBUNTU-CVE-2026-50538"],"upstream":["UBUNTU-CVE-2026-50538"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8494-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-50538"}],"affected":[{"package":{"name":"libvncserver","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libvncserver?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.13+dfsg-3ubuntu0.2"}]}],"versions":["0.9.13+dfsg-3","0.9.13+dfsg-3build1","0.9.13+dfsg-3build2","0.9.13+dfsg-3ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libvncclient1","binary_version":"0.9.13+dfsg-3ubuntu0.2"},{"binary_name":"libvncserver1","binary_version":"0.9.13+dfsg-3ubuntu0.2"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2026-50538","severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"medium","type":"Ubuntu"}]}],"ecosystem":"Ubuntu:22.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8494-1.json"}},{"package":{"name":"libvncserver","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/libvncserver?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.14+dfsg-1ubuntu0.2"}]}],"versions":["0.9.14+dfsg-1","0.9.14+dfsg-1build1","0.9.14+dfsg-1build2","0.9.14+dfsg-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libvncclient1","binary_version":"0.9.14+dfsg-1ubuntu0.2"},{"binary_name":"libvncserver1","binary_version":"0.9.14+dfsg-1ubuntu0.2"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:24.04:LTS","cves":[{"id":"CVE-2026-50538","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8494-1.json"}},{"package":{"name":"libvncserver","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/libvncserver?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.15+dfsg-1ubuntu0.2"}]}],"versions":["0.9.14+dfsg-1build2","0.9.15+dfsg-1","0.9.15+dfsg-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libvncclient1","binary_version":"0.9.15+dfsg-1ubuntu0.2"},{"binary_name":"libvncserver1","binary_version":"0.9.15+dfsg-1ubuntu0.2"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:25.10","cves":[{"id":"CVE-2026-50538","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8494-1.json"}},{"package":{"name":"libvncserver","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/libvncserver?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.15+dfsg-3ubuntu0.2"}]}],"versions":["0.9.15+dfsg-1","0.9.15+dfsg-2","0.9.15+dfsg-3","0.9.15+dfsg-3ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libvncclient1","binary_version":"0.9.15+dfsg-3ubuntu0.2"},{"binary_name":"libvncserver1","binary_version":"0.9.15+dfsg-3ubuntu0.2"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:26.04:LTS","cves":[{"id":"CVE-2026-50538","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8494-1.json"}}],"schema_version":"1.9.0"}