{"id":"CVE-2021-20181","details":"A race condition flaw was found in the 9pfs server implementation of QEMU up to and including 5.2.0. This flaw allows a malicious 9p client to cause a use-after-free error, potentially escalating their privileges on the system. The highest threat from this vulnerability is to confidentiality, integrity as well as system availability.","modified":"2026-03-18T11:42:43.097978Z","published":"2021-05-13T16:15:07.653Z","related":["SUSE-SU-2021:0521-1","SUSE-SU-2021:1240-1","SUSE-SU-2021:1241-1","SUSE-SU-2021:1242-1","SUSE-SU-2021:1244-1","SUSE-SU-2021:1245-1","SUSE-SU-2021:1305-1","SUSE-SU-2021:14704-1","SUSE-SU-2021:14706-1","openSUSE-SU-2021:0363-1","openSUSE-SU-2024:11287-1"],"references":[{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2021/02/msg00024.html"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20210720-0009/"},{"type":"ADVISORY","url":"https://www.zerodayinitiative.com/advisories/ZDI-21-159/"},{"type":"FIX","url":"https://bugzilla.redhat.com/show_bug.cgi?id=1927007"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/qemu/qemu","events":[{"introduced":"0"},{"last_affected":"553032db17440f8de011390e5a1cfddd13751b0b"},{"introduced":"0"},{"last_affected":"c25df57ae8f9fe1c72eee2dab37d76d904ac382e"},{"introduced":"0"},{"last_affected":"7c949c53e936aa3a658d84ab53bae5cadaa5d59c"}],"database_specific":{"versions":[{"introduced":"0"},{"last_affected":"5.2.0"},{"introduced":"0"},{"last_affected":"9.0"},{"introduced":"0"},{"last_affected":"10.0"}]}}],"versions":["v0.1.0","v0.1.1","v0.1.3","v0.1.4","v0.1.5","v0.1.6","v0.11.0-rc0","v0.12.0-rc0","v0.13.0-rc0","v0.14.0-rc0","v0.15.0-rc0","v0.2.0","v0.3.0","v0.4.0","v0.4.1","v0.4.2","v0.4.3","v0.4.4","v0.5.0","v1.0","v1.0-rc0","v1.0-rc1","v1.0-rc2","v1.0-rc3","v1.0-rc4","v1.1-rc0","v1.1-rc1","v1.1-rc2","v1.1.0","v1.1.0-rc2","v1.1.0-rc3","v1.1.0-rc4","v1.2.0","v1.2.0-rc0","v1.2.0-rc1","v1.2.0-rc2","v1.2.0-rc3","v1.3.0","v1.3.0-rc0","v1.3.0-rc1","v1.3.0-rc2","v1.4.0","v1.4.0-rc0","v1.4.0-rc1","v1.4.0-rc2","v1.5.0","v1.5.0-rc0","v1.5.0-rc1","v1.5.0-rc2","v1.5.0-rc3","v1.6.0","v1.6.0-rc0","v1.6.0-rc1","v1.6.0-rc2","v1.6.0-rc3","v1.7.0","v1.7.0-rc0","v1.7.0-rc1","v1.7.0-rc2","v2.0.0","v2.0.0-rc0","v2.0.0-rc1","v2.0.0-rc2","v2.0.0-rc3","v2.1.0","v2.1.0-rc0","v2.1.0-rc1","v2.1.0-rc2","v2.1.0-rc3","v2.1.0-rc4","v2.1.0-rc5","v2.10.0","v2.10.0-rc0","v2.10.0-rc1","v2.10.0-rc2","v2.10.0-rc3","v2.10.0-rc4","v2.11.0","v2.11.0-rc0","v2.11.0-rc1","v2.11.0-rc2","v2.11.0-rc3","v2.11.0-rc4","v2.11.0-rc5","v2.12.0","v2.12.0-rc0","v2.12.0-rc1","v2.12.0-rc2","v2.12.0-rc3","v2.12.0-rc4","v2.2.0","v2.2.0-rc0","v2.2.0-rc1","v2.2.0-rc2","v2.2.0-rc3","v2.2.0-rc4","v2.2.0-rc5","v2.3.0","v2.3.0-rc0","v2.3.0-rc1","v2.3.0-rc2","v2.3.0-rc3","v2.3.0-rc4","v2.4.0","v2.4.0-rc0","v2.4.0-rc1","v2.4.0-rc2","v2.4.0-rc3","v2.4.0-rc4","v2.5.0","v2.5.0-rc0","v2.5.0-rc1","v2.5.0-rc2","v2.5.0-rc3","v2.5.0-rc4","v2.6.0","v2.6.0-rc0","v2.6.0-rc1","v2.6.0-rc2","v2.6.0-rc3","v2.6.0-rc4","v2.6.0-rc5","v2.7.0","v2.7.0-rc0","v2.7.0-rc1","v2.7.0-rc2","v2.7.0-rc3","v2.7.0-rc4","v2.7.0-rc5","v2.8.0","v2.8.0-rc0","v2.8.0-rc1","v2.8.0-rc2","v2.8.0-rc3","v2.8.0-rc4","v2.9.0","v2.9.0-rc0","v2.9.0-rc1","v2.9.0-rc2","v2.9.0-rc3","v2.9.0-rc4","v2.9.0-rc5","v3.0.0","v3.0.0-rc0","v3.0.0-rc1","v3.0.0-rc2","v3.0.0-rc3","v3.0.0-rc4","v3.1.0","v3.1.0-rc0","v3.1.0-rc1","v3.1.0-rc2","v3.1.0-rc3","v3.1.0-rc4","v3.1.0-rc5","v4.0.0","v4.0.0-rc0","v4.0.0-rc1","v4.0.0-rc2","v4.0.0-rc3","v4.0.0-rc4","v4.1.0","v4.1.0-rc0","v4.1.0-rc1","v4.1.0-rc2","v4.1.0-rc3","v4.1.0-rc4","v4.1.0-rc5","v4.2.0","v4.2.0-rc0","v4.2.0-rc1","v4.2.0-rc2","v4.2.0-rc3","v4.2.0-rc4","v4.2.0-rc5","v5.0.0","v5.0.0-rc0","v5.0.0-rc1","v5.0.0-rc2","v5.0.0-rc3","v5.0.0-rc4","v5.1.0","v5.1.0-rc0","v5.1.0-rc1","v5.1.0-rc2","v5.1.0-rc3","v5.2.0","v5.2.0-rc0","v5.2.0-rc1","v5.2.0-rc2","v5.2.0-rc3","v5.2.0-rc4"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-20181.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H"}]}