CVE-2021-3929
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.67%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 8.2 HIGHCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 0.67% probability · 50th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-416
- Affected
- qemu/qemu · fedoraproject/fedora
- Source
- secalert@redhat.com
References
- https://access.redhat.com/security/cve/CVE-2021-3929Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2020298Issue Tracking, Patch, Third Party Advisory
- https://gitlab.com/qemu-project/qemu/-/commit/736b01642d85be832385Patch, Third Party Advisory
- https://gitlab.com/qemu-project/qemu/-/issues/556Issue Tracking, Third Party Advisory
- https://gitlab.com/qemu-project/qemu/-/issues/782Exploit, Issue Tracking, Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XHNN7QJCEQH7AQG5AQP2GEFAQE6K635I/
- https://access.redhat.com/security/cve/CVE-2021-3929Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2020298Issue Tracking, Patch, Third Party Advisory
- https://gitlab.com/qemu-project/qemu/-/commit/736b01642d85be832385Patch, Third Party Advisory
- https://gitlab.com/qemu-project/qemu/-/issues/556Issue Tracking, Third Party Advisory
- https://gitlab.com/qemu-project/qemu/-/issues/782Exploit, Issue Tracking, Patch, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XHNN7QJCEQH7AQG5AQP2GEFAQE6K635I/
- https://security.netapp.com/advisory/ntap-20250228-0010/
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.