{"id":"USN-8463-1","summary":"libvncserver vulnerabilities","details":"It was discovered that LibVNCServer had a memory leak in the client cleanup\nfunction. An attacker could possibly use this issue to cause LibVNCServer\nto consume memory, leading to a denial of service. This issue only affected\nUbuntu 22.04 LTS. (CVE-2020-29260)\n\nIt was discovered that LibVNCServer did not properly validate bounds when\nhandling UltraZip encoding subrectangles. A remote attacker could possibly\nuse this issue to obtain sensitive information or cause a denial of\nservice. This issue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and\nUbuntu 25.04. (CVE-2026-32853)\n\nIt was discovered that LibVNCServer did not properly validate return values\nin the HTTP proxy handlers. A remote attacker could possibly use this issue\nto cause LibVNCServer to crash, resulting in a denial of service. This\nissue only affected Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 25.04.\n(CVE-2026-32854)\n\nIt was discovered that LibVNCServer did not properly handle Tight encoding\ngradient filter rectangles. A remote attacker could use this issue to cause\nLibVNCServer to crash, resulting in a denial of service, or possibly\nexecute arbitrary code. (CVE-2026-44988)","modified":"2026-06-23T22:14:21.491003071Z","published":"2026-06-23T14:46:54Z","related":["UBUNTU-CVE-2020-29260","UBUNTU-CVE-2026-32853","UBUNTU-CVE-2026-32854","UBUNTU-CVE-2026-44988"],"upstream":["CVE-2020-29260","CVE-2026-32853","CVE-2026-32854","CVE-2026-44988","UBUNTU-CVE-2020-29260","UBUNTU-CVE-2026-32853","UBUNTU-CVE-2026-32854","UBUNTU-CVE-2026-44988"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8463-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-29260"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-32853"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-32854"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-44988"}],"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-3ubuntu0.1"}]}],"versions":["0.9.13+dfsg-3","0.9.13+dfsg-3build1","0.9.13+dfsg-3build2"],"ecosystem_specific":{"availability":"No subscription 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