{"schema_version":"1.7.5","id":"CVE-2021-3527","published":"2021-05-26T22:15:08.267Z","modified":"2026-07-09T00:37:18.468121Z","related":["SUSE-SU-2021:14848-1","SUSE-SU-2021:2789-1","SUSE-SU-2021:2813-1","SUSE-SU-2021:2858-1","SUSE-SU-2021:3575-1","SUSE-SU-2021:3613-1","SUSE-SU-2021:3614-1","SUSE-SU-2021:3635-1","openSUSE-SU-2021:1202-1","openSUSE-SU-2021:2789-1","openSUSE-SU-2021:2858-1","openSUSE-SU-2021:3614-1","openSUSE-SU-2024:11287-1"],"details":"A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB packets are combined into a single, large transfer request, to reduce the overhead and improve performance. The combined size of the bulk transfer is used to dynamically allocate a variable length array (VLA) on the stack without proper validation. Since the total size is not bounded, a malicious guest could use this flaw to influence the array length and cause the QEMU process to perform an excessive allocation on the stack, resulting in a denial of service.","affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/qemu/qemu","events":[{"introduced":"0"},{"last_affected":"609d7596524ab204ccd71ef42c9eee4c7c338ea4"}],"database_specific":{"cpe":"cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"last_affected":"6.0.0"}],"source":"CPE_RANGE"}}],"versions":["v6.0.0","v6.0.0-rc5","v6.0.0-rc4","v6.0.0-rc3","v6.0.0-rc2","v6.0.0-rc1","v6.0.0-rc0","v5.2.0","v5.2.0-rc4","v5.2.0-rc3","v5.2.0-rc2","v5.2.0-rc1","v5.2.0-rc0","v5.0.0","v5.1.0","v5.1.0-rc3","v5.1.0-rc2","v5.1.0-rc1","v5.1.0-rc0","v4.2.0","v5.0.0-rc4","v5.0.0-rc3","v5.0.0-rc2","v5.0.0-rc1","v5.0.0-rc0","v4.2.0-rc5","v4.2.0-rc4","v4.2.0-rc3","v4.2.0-rc2","v4.2.0-rc1","v4.2.0-rc0","v4.1.0","v4.0.0","v4.1.0-rc5","v4.1.0-rc4","v4.1.0-rc3","v4.1.0-rc2","v4.1.0-rc1","v4.1.0-rc0","v4.0.0-rc4","v4.0.0-rc3","v4.0.0-rc2","v4.0.0-rc1","v3.1.0","v4.0.0-rc0","v3.0.0","v3.1.0-rc5","v3.1.0-rc4","v3.1.0-rc3","v3.1.0-rc2","v3.1.0-rc1","v3.1.0-rc0","v3.0.0-rc4","v3.0.0-rc3","v3.0.0-rc2","v3.0.0-rc1","v3.0.0-rc0","v2.12.0","v2.12.0-rc4","v2.12.0-rc3","v2.12.0-rc2","v2.12.0-rc1","v2.12.0-rc0","v2.11.0","v2.11.0-rc5","v2.11.0-rc4","v2.11.0-rc3","v2.11.0-rc2","v2.11.0-rc1","v2.11.0-rc0","v2.10.0","v2.10.0-rc4","v2.10.0-rc3","v2.10.0-rc2","v2.10.0-rc1","v2.9.0","v2.10.0-rc0","v2.9.0-rc5","v2.9.0-rc4","v2.9.0-rc3","v2.9.0-rc2","v2.9.0-rc1","v2.8.0","v2.9.0-rc0","v2.8.0-rc4","v2.8.0-rc3","v2.8.0-rc2","v2.8.0-rc1","v2.8.0-rc0","v2.7.0","v2.7.0-rc5","v2.7.0-rc4","v2.7.0-rc3","v2.7.0-rc2","v2.6.0","v2.7.0-rc1","v2.7.0-rc0","v2.6.0-rc5","v2.6.0-rc4","v2.6.0-rc3","v2.6.0-rc2","v2.6.0-rc1","v2.6.0-rc0","v2.5.0","v2.5.0-rc4","v2.5.0-rc3","v2.5.0-rc2","v2.5.0-rc1","v2.5.0-rc0","v2.4.0","v2.4.0-rc4","v2.4.0-rc3","v2.3.0","v2.4.0-rc2","v2.4.0-rc1","v2.4.0-rc0","v2.3.0-rc4","v2.3.0-rc3","v2.3.0-rc2","v2.3.0-rc1","v2.3.0-rc0","v2.2.0","v2.2.0-rc3","v2.2.0-rc5","v2.2.0-rc4","v2.2.0-rc2","v2.2.0-rc1","v2.2.0-rc0","v2.1.0","v2.1.0-rc5","v2.1.0-rc4","v2.1.0-rc2","v2.1.0-rc3","v2.0.0","v2.1.0-rc1","v2.1.0-rc0","v2.0.0-rc3","v2.0.0-rc2","v2.0.0-rc1","v2.0.0-rc0","v1.7.0","v1.7.0-rc2","v1.7.0-rc1","v1.7.0-rc0","v1.6.0","v1.6.0-rc3","v1.6.0-rc2","v1.6.0-rc1","v1.6.0-rc0","v1.5.0","v1.5.0-rc3","v1.5.0-rc2","v1.5.0-rc1","v1.5.0-rc0","v1.4.0","v1.4.0-rc2","v1.4.0-rc1","v1.4.0-rc0","v1.3.0","v1.3.0-rc2","v1.3.0-rc1","v1.3.0-rc0","v1.2.0","v1.2.0-rc3","v1.2.0-rc2","v1.2.0-rc1","v1.2.0-rc0","v1.1.0","v1.1.0-rc4","v1.1.0-rc3","v1.1.0-rc2","v1.1-rc2","v1.1-rc1","v1.1-rc0","v1.0","v1.0-rc4","v1.0-rc3","v1.0-rc2","v1.0-rc1","v1.0-rc0","v0.14.0-rc0","v0.13.0-rc0","v0.12.0-rc0","v0.11.0-rc0","v0.5.0","v0.4.4","v0.4.3","v0.4.2","v0.4.1","v0.4.0","v0.3.0","v0.2.0","v0.1.6","v0.1.5","v0.1.4","v0.1.3","v0.1.1","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-3527.json"}},{"ranges":[{"type":"GIT","repo":"https://gitlab.com/qemu-project/qemu","events":[{"introduced":"0"},{"last_affected":"609d7596524ab204ccd71ef42c9eee4c7c338ea4"},{"fixed":"05a40b172e4d691371534828078be47e7fff524c"},{"fixed":"7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986"}],"database_specific":{"cpe":"cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"last_affected":"6.0.0"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["v6.0.0","v6.0.0-rc5","v6.0.0-rc4","v6.0.0-rc3","v6.0.0-rc2","v6.0.0-rc1","v6.0.0-rc0","v5.2.0","v5.2.0-rc4","v5.2.0-rc3","v5.2.0-rc2","v5.2.0-rc1","v5.2.0-rc0","v5.0.0","v5.1.0","v5.1.0-rc3","v5.1.0-rc2","v5.1.0-rc1","v5.1.0-rc0","v4.2.0","v5.0.0-rc4","v5.0.0-rc3","v5.0.0-rc2","v5.0.0-rc1","v5.0.0-rc0","v4.2.0-rc5","v4.2.0-rc4","v4.2.0-rc3","v4.2.0-rc2","v4.2.0-rc1","v4.2.0-rc0","v4.1.0","v4.0.0","v4.1.0-rc5","v4.1.0-rc4","v4.1.0-rc3","v4.1.0-rc2","v4.1.0-rc1","v4.1.0-rc0","v4.0.0-rc4","v4.0.0-rc3","v4.0.0-rc2","v4.0.0-rc1","v3.1.0","v4.0.0-rc0","v3.0.0","v3.1.0-rc5","v3.1.0-rc4","v3.1.0-rc3","v3.1.0-rc2","v3.1.0-rc1","v3.1.0-rc0","v3.0.0-rc4","v3.0.0-rc3","v3.0.0-rc2","v3.0.0-rc1","v3.0.0-rc0","v2.12.0","v2.12.0-rc4","v2.12.0-rc3","v2.12.0-rc2","v2.12.0-rc1","v2.12.0-rc0","v2.11.0","v2.11.0-rc5","v2.11.0-rc4","v2.11.0-rc3","v2.11.0-rc2","v2.11.0-rc1","v2.11.0-rc0","v2.10.0","v2.10.0-rc4","v2.10.0-rc3","v2.10.0-rc2","v2.10.0-rc1","v2.9.0","v2.10.0-rc0","v2.9.0-rc5","v2.9.0-rc4","v2.9.0-rc3","v2.9.0-rc2","v2.9.0-rc1","v2.8.0","v2.9.0-rc0","v2.8.0-rc4","v2.8.0-rc3","v2.8.0-rc2","v2.8.0-rc1","v2.8.0-rc0","v2.7.0","v2.7.0-rc5","v2.7.0-rc4","v2.7.0-rc3","v2.7.0-rc2","v2.6.0","v2.7.0-rc1","v2.7.0-rc0","v2.6.0-rc5","v2.6.0-rc4","v2.6.0-rc3","v2.6.0-rc2","v2.6.0-rc1","v2.6.0-rc0","v2.5.0","v2.5.0-rc4","v2.5.0-rc3","v2.5.0-rc2","v2.5.0-rc1","v2.5.0-rc0","v2.4.0","v2.4.0-rc4","v2.4.0-rc3","v2.3.0","v2.4.0-rc2","v2.4.0-rc1","v2.4.0-rc0","v2.3.0-rc4","v2.3.0-rc3","v2.3.0-rc2","v2.3.0-rc1","v2.3.0-rc0","v2.2.0","v2.2.0-rc3","v2.2.0-rc5","v2.2.0-rc4","v2.2.0-rc2","v2.2.0-rc1","v2.2.0-rc0","v2.1.0","v2.1.0-rc5","v2.1.0-rc4","v2.1.0-rc2","v2.1.0-rc3","v2.0.0","v2.1.0-rc1","v2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