{"id":"CVE-2021-4145","details":"A NULL pointer dereference issue was found in the block mirror layer of QEMU in versions prior to 6.2.0. The `self` pointer is dereferenced in mirror_wait_on_conflicts() without ensuring that it's not NULL. A malicious unprivileged user within the guest could use this flaw to crash the QEMU process on the host when writing data reaches the threshold of mirroring node.","modified":"2026-04-11T18:45:30.531581Z","published":"2022-01-25T20:15:08.657Z","related":["ALSA-2022:1759"],"references":[{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/202208-27"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20220311-0004/"},{"type":"FIX","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2034602"},{"type":"FIX","url":"https://gitlab.com/qemu-project/qemu/-/commit/66fed30c9cd11854fc878a4eceb507e915d7c9cd"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/qemu/qemu","events":[{"introduced":"0"},{"last_affected":"f9baca549e44791be0dd98de15add3d8452a8af0"},{"introduced":"0"},{"last_affected":"e77c8b8b8e933414ef07dbed04e02973fccffeb0"},{"introduced":"0"},{"last_affected":"f2da205cb4142259d9bc6b9d4596ebbe2426fe49"},{"introduced":"0"},{"last_affected":"bccabb3a5d60182645c7749e89f21a9ff307a9eb"},{"introduced":"0"},{"last_affected":"703e8cd6189cf699c8d5c094bc68b5f3afa6ad71"},{"introduced":"0"},{"last_affected":"ecf2706e271fa705621f0d5ad9517fe15a22bf22"},{"introduced":"0"},{"last_affected":"c1eb2ddf0f8075faddc5f7c3d39feae3e8e9d6b4"}],"database_specific":{"versions":[{"introduced":"0"},{"last_affected":"6.1.0-NA"},{"introduced":"0"},{"last_affected":"6.1.0-rc0"},{"introduced":"0"},{"last_affected":"6.1.0-rc1"},{"introduced":"0"},{"last_affected":"6.1.0-rc2"},{"introduced":"0"},{"last_affected":"6.1.0-rc3"},{"introduced":"0"},{"last_affected":"6.1.0-rc4"},{"introduced":"0"},{"last_affected":"8.0"}]}},{"type":"GIT","repo":"https://gitlab.com/qemu-project/qemu","events":[{"introduced":"0"},{"fixed":"66fed30c9cd11854fc878a4eceb507e915d7c9cd"}]}],"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","v0.2.0","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","v6.0.0","v6.0.0-rc0","v6.0.0-rc1","v6.0.0-rc2","v6.0.0-rc3","v6.0.0-rc4","v6.0.0-rc5","v6.1.0","v6.1.0-rc0","v6.1.0-rc1","v6.1.0-rc2","v6.1.0-rc3","v6.1.0-rc4","v6.2.0","v6.2.0-rc0","v6.2.0-rc1","v6.2.0-rc3","v6.2.0-rc4","v7.0.0","v7.0.0-rc0","v7.0.0-rc1","v7.0.0-rc2","v7.0.0-rc3","v7.0.0-rc4","v7.1.0","v7.1.0-rc0","v7.1.0-rc1","v7.1.0-rc2","v7.1.0-rc3","v7.1.0-rc4","v7.2.0","v7.2.0-rc0","v7.2.0-rc1","v7.2.0-rc2","v7.2.0-rc3","v7.2.0-rc4","v8.0.0","v8.0.0-rc0","v8.0.0-rc1","v8.0.0-rc2","v8.0.0-rc3","v8.0.0-rc4"],"database_specific":{"vanir_signatures_modified":"2026-04-11T18:45:30Z","source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-4145.json","vanir_signatures":[{"id":"CVE-2021-4145-0b3d3b8a","digest":{"function_hash":"111420676610769034413802176203666229979","length":765},"signature_type":"Function","target":{"function":"mirror_wait_on_conflicts","file":"block/mirror.c"},"deprecated":false,"source":"https://gitlab.com/qemu-project/qemu@66fed30c9cd11854fc878a4eceb507e915d7c9cd","signature_ve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