CVE-2022-49568
MediumIn the Linux kernel, the following vulnerability has been resolved: KVM: Don't null dereference ops->destroy A KVM device cleanup happens in either of two callbacks: 1) destroy() which is called when the VM is being destroyed; 2) release() which is called when a device fd is closed. Most KVM devices use 1) but Book3s's interrupt controller KVM devices (XICS, XIVE, XIVE-native) use 2) as they need to close and reopen during the machine execution. The error handling in kvm_ioctl_create_device() assumes destroy() is always defined which leads to NULL dereference as discovered by Syzkaller. This adds a checks for destroy!=NULL and adds a missing release(). This is not changing kvm_destroy_devices() as devices with defined release() should have been removed from the KVM devices list by then.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-476CVE-2022-49568 is a NULL Pointer Dereference vulnerability
What is NULL Pointer Dereference?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE
Affected versions
Linux kernel versions
3.10
and later are affected. Fixed in
5.4.210,
5.10.134,
5.15.58,
5.18.15,
5.19
and their respective stable series.
References
The following references provide additional information about CVE-2022-49568 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/170465715a60cbb7876e6b961b21bd3225469da8
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PatchKernel patch commithttps://git.kernel.org/stable/c/3616776bc51cd3262bb1be60cc01c72e0a1959cf
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PatchKernel patch commithttps://git.kernel.org/stable/c/d4a5a79b780891c5cbdfdc6124d46fdf8d13dba1
Frequently asked questions
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What is CVE-2022-49568?
CVE-2022-49568 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 3.10 onward and has been patched in 5.4.210, 5.10.134, 5.15.58 and others. CVE-2022-49568 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2022-49568?
CVE-2022-49568 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2022-49568?
Yes — CVE-2022-49568 has been patched. Fixed versions include 5.4.210, 5.10.134, 5.15.58 and others. If you are running Linux kernel 3.10 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2022-49568 actively exploited?
No — CVE-2022-49568 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is NULL Pointer Dereference (CWE-476)?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →