Home/CVE/A NULL pointer dereference issue was found in the block mirror layer of QEMU in versions prior to 6.2.0. The `self` poin
CVE

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` poin

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.

MEDIUM · CVSS 6.5 EPSS 0.00058
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules1 YARA rules0
⬡

Weakness Classification

CWE-476NULL Pointer Dereference
CWE-476NULL Pointer Dereference
▤

Affected Products & Versions

2
qemuall versions
redhat enterprise linuxall versions
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
productmediumPotentially Suspicious Usage Of Qemu
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · secalert@redhat.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD25 Jan 2022 · 08:15 PM
CVSS VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
⚑

Vendor Advisories

2
msrcCVE-2021-4145
rhsaRHSA-2022:1759Moderate
🔗

References & Sources

4
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.redhat.com/show_bug.cgi?id=2034602Issue TrackingPatchThird Party Advisory
https://gitlab.com/qemu-project/qemu/-/commit/66fed30c9cd11854fc878a4eceb507e915d7c9cdPatchThird Party Advisory
https://security.gentoo.org/glsa/202208-27Third Party Advisory
https://security.netapp.com/advisory/ntap-20220311-0004/Third Party Advisory
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