{"id":"CVE-2021-45464","aliases":["EUVD-2021-32230","GHSA-42pc-9g8v-prfm","UBUNTU-CVE-2021-45464","USN-8172-1"],"status":"published","title":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci...","description":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.","severity":{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-11","score":0.00378,"percentile":0.3223,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-787"],"published":"2023-04-15T00:00:00Z","modified":"2026-06-25T13:32:31Z","fixes":[{"ecosystem":"Ubuntu:Pro:16.04:LTS","package":"kvmtool","fixed_in":["0.20151104-1ubuntu0.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"kvmtool","fixed_in":["0.20170904-1ubuntu0.18.04.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:20.04:LTS","package":"kvmtool","fixed_in":["0.20170904-1ubuntu0.20.04.1~esm1"],"sources":["osv"]},{"ecosystem":"Ubuntu:Pro:22.04:LTS","package":"kvmtool","fixed_in":["0.20170904-1.1ubuntu0.1~esm2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20151104-1ubuntu0.1~esm1"}]}],"versions":["0.20150908-1","0.20151104-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20170904-1ubuntu0.18.04.1~esm1"}]}],"versions":["0.20161128-1","0.20170904-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20170904-1ubuntu0.20.04.1~esm1"}]}],"versions":["0.20170904-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20170904-1.1ubuntu0.1~esm2"}]}],"versions":["0.20170904-1.1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20151104-1ubuntu0.1~esm1"}]}],"versions":["0.20150908-1","0.20151104-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20170904-1ubuntu0.18.04.1~esm1"}]}],"versions":["0.20161128-1","0.20170904-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20170904-1ubuntu0.20.04.1~esm1"}]}],"versions":["0.20170904-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"kvmtool","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.20170904-1.1ubuntu0.1~esm2"}]}],"versions":["0.20170904-1.1"]}],"products":[{"vendor":"kvmtool_project","product":"kvmtool"}],"references":[{"url":"https://cdn.discordapp.com/attachments/921419715170164776/921882173517230100/exploit.c","tags":["x_transferred","Broken Link"]},{"url":"https://git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/log/","tags":["x_transferred","Patch"]},{"url":"https://www.kalmarunionen.dk/writeups/2021/hxp-2021/lkvm/","tags":["x_transferred","Exploit","Third Party Advisory","report"]},{"url":"https://git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/commit/?id=39181fc6429f4e9e71473284940e35857b42772a","tags":["x_transferred","Patch"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-45464"},{"url":"https://git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/log"},{"url":"https://www.kalmarunionen.dk/writeups/2021/hxp-2021/lkvm"},{"url":"https://github.com/advisories/GHSA-42pc-9g8v-prfm"},{"url":"https://ubuntu.com/security/CVE-2021-45464","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-45464","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-8172-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2023-2861","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-45464","description":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.","status":"published","published":"2023-04-15T00:00:00Z","modified":"2025-02-06T16:05:11.019Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:33:02.580561Z"}],"euvd":[{"id":"EUVD-2021-32230","description":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.","status":"published","published":"2023-04-15T00:00:00Z","modified":"2025-02-06T16:05:11Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-03T00:04:03.312509Z"}],"ghsa":[{"id":"GHSA-42pc-9g8v-prfm","title":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci...","description":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.","status":"published","published":"2023-04-16T00:30:25Z","modified":"2024-04-04T03:30:13Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:56:15.423381Z"}],"nvd":[{"id":"CVE-2021-45464","description":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.","status":"published","published":"2023-04-15T23:15:13.76Z","modified":"2026-06-17T04:13:25.017Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"primary"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-787"],"updated_at":"2026-11-02T14:07:07.764332Z"}],"osv":[{"id":"UBUNTU-CVE-2021-45464","description":"kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.","status":"published","published":"2023-04-15T23:15:00Z","modified":"2026-04-14T09:50:49.189065Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high"},{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:54:30.277322Z"},{"id":"USN-8172-1","title":"kvmtool vulnerabilities","description":"It was discovered that kvmtool did not properly manage memory under certain\ncircumstances. A malicious guest attacker could use this issue to cause\nkvmtool to crash, leading to a denial of service, or possibly execute\narbitrary code on the host system. (CVE-2021-45464)\n\nIt was discovered that kvmtool incorrectly handled the 9p passthrough file\nsystem. A malicious guest attacker could possibly use this issue to open\nspecial files, escape the exported 9p tree, and execute arbitrary code on\nthe host system. (CVE-2023-2861)","status":"published","published":"2026-04-13T18:27:37Z","modified":"2026-06-25T13:32:31.930840306Z","updated_at":"2026-11-02T16:58:22.951676Z"}]}}