CVE-2021-3929
HIGH severity · CVSS 8.2 · Use-after-free
8.2CVSS HIGH
Summary
A DMA reentrancy issue was found in the NVM Express Controller (NVME) emulation in QEMU. This CVE is similar to CVE-2021-3750 and, just like it, when the reentrancy write triggers the reset function nvme_ctrl_reset(), data structs will be freed leading to a use-after-free issue. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition or, potentially, executing arbitrary code within the context of the QEMU process on the host.
Impact & exploitability
Attack vectorLocal
Attack complexityLow
Privileges requiredHigh
User interactionNone
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
Exploit probability (EPSS)1%
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Affected products we track (1)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Official patch: https://bugzilla.redhat.com/show_bug.cgi?id=2020298 ↗
Additional information
- NVD record
- https://bugzilla.redhat.com/show_bug.cgi?id=2020298Patch
- https://gitlab.com/qemu-project/qemu/-/commit/736b01642d85be832385Patch
- https://gitlab.com/qemu-project/qemu/-/issues/782Patch
- https://access.redhat.com/security/cve/CVE-2021-3929Advisory
- https://gitlab.com/qemu-project/qemu/-/issues/556Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XHNN7QJCEQH7AQG5AQP2GEFAQE6K635I/