REDHAT-BUG-2035002: Null Pointer Dereference
First published: Wed Dec 22 2021(Updated: )
A NULL pointer dereference was found in the ACPI code of QEMU. The flaw lies in hw/acpi/pcihp.c in pci_write() where the `bus` pointer is used without checking if it's NULL, probably because an invalid selector was supplied. A malicious privileged user within the guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition. Upstream issue: <a href="https://gitlab.com/qemu-project/qemu/-/issues/770">https://gitlab.com/qemu-project/qemu/-/issues/770</a> Upstream patch: <a href="https://lists.nongnu.org/archive/html/qemu-devel/2021-12/msg01491.html">https://lists.nongnu.org/archive/html/qemu-devel/2021-12/msg01491.html</a>
| Affected Software | Affected Version | How to fix |
|---|---|---|
| QEMU |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- https://gitlab.com/qemu-project/qemu/-/issues/770
- https://lists.nongnu.org/archive/html/qemu-devel/2021-12/msg01491.html
- https://www.mail-archive.com/qemu-devel@nongnu.org/msg857944.html
- https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=2036574
- https://access.redhat.com/errata/RHSA-2022:1759
- https://access.redhat.com/security/cve/cve-2021-4158
- https://access.redhat.com/errata/RHSA-2022:7967
- https://bugzilla.redhat.com/show_bug.cgi?id=2035002
Frequently Asked Questions
What is the severity of REDHAT-BUG-2035002?
The severity of REDHAT-BUG-2035002 is classified as critical due to the potential for a malicious privileged user to crash the system.
How do I fix REDHAT-BUG-2035002?
To fix REDHAT-BUG-2035002, update to the latest version of QEMU that addresses this NULL pointer dereference vulnerability.
What causes the vulnerability REDHAT-BUG-2035002?
REDHAT-BUG-2035002 is caused by a NULL pointer dereference in the ACPI code of QEMU when the `bus` pointer is used without validation.
Who is affected by REDHAT-BUG-2035002?
Users running vulnerable versions of QEMU, especially within a guest environment, are affected by REDHAT-BUG-2035002.
Can a guest user exploit REDHAT-BUG-2035002?
Yes, a malicious privileged user within the guest can exploit REDHAT-BUG-2035002 to crash the QEMU instance.
- agent/type
- agent/references
- agent/last-modified-date
- agent/first-publish-date
- collector/redhat-bugzilla
- source/Red Hat
- alias/CVE-2021-4158
- agent/weakness
- agent/severity
- agent/description
- agent/event
- agent/source
- agent/softwarecombine
- agent/tags
- agent/guess-ai
- agent/software-canonical-lookup
- agent/software-canonical-lookup-request
- vendor/qemu
- canonical/qemu