NULL pointer dereference in Qemu
CVE-2021-4145
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.
EPSS: 0.004 (31.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.
Affected products
- Qemu — versions 6.1.0
- Redhat Enterprise_linux — versions 8.0
- N/a Qemu — versions qemu-kvm 6.2.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- secalert@redhat.com (Patch, Third Party Advisory, x_refsource_MISC, Issue Tracking)
- secalert@redhat.com (Patch, Third Party Advisory, x_refsource_MISC)
- secalert@redhat.com (x_refsource_CONFIRM, Third Party Advisory)
- secalert@redhat.com (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2021-4145?
- CVE-2021-4145 is a medium-severity vulnerability in Qemu, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2022-01-25.
- How severe is CVE-2021-4145?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2021-4145 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.