What is CVE-2020-8834?

CVE-2020-8834 is a Medium severity Linux kernel vulnerability with a CVSS score of 6.5 out of 10. CVE-2020-8834 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2020-8834?

CVE-2020-8834 has a CVSS score of 6.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.

Is there a patch available for CVE-2020-8834?

No patch is currently available for CVE-2020-8834. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2020-8834 actively exploited?

CVE-2020-8834 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2020-8834

Medium

KVM in the Linux kernel on Power8 processors has a conflicting use of HSTATE_HOST_R1 to store r1 state in kvmppc_hv_entry plus in kvmppc_{save,restore}_tm, leading to a stack corruption. Because of this, an attacker with the ability run code in kernel space of a guest VM can cause the host kernel to panic. There were two commits that, according to the reporter, introduced the vulnerability: f024ee098476 ("KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures") 87a11bb6a7f7 ("KVM: PPC: Book3S HV: Work around XER[SO] bug in fake suspend mode") The former landed in 4.8, the latter in 4.17. This was fixed without realizing the impact in 4.18 with the following three commits, though it's believed the first is the only strictly necessary commit: 6f597c6b63b6 ("KVM: PPC: Book3S PR: Add guest MSR parameter for kvmppc_save_tm()/kvmppc_restore_tm()") 7b0e827c6970 ("KVM: PPC: Book3S HV: Factor fake-suspend handling out of kvmppc_save/restore_tm") 009c872a8bc4 ("KVM: PPC: Book3S PR: Move kvmppc_save_tm/kvmppc_restore_tm to separate file")

Package Linux Kernel

Published 2020-04-09

Last modified 2024-11-21

CVSS version 3.1

Patch available

Awaiting data

CVSS 3.1 score

6.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

Low

Integrity

None

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Weakness type

CWE-368

CVE-2020-8834 is classified as CWE-368

See CWE-368 on MITRE CWE for full details on this weakness type.

References

The following references provide additional information about CVE-2020-8834 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Lists
http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00035.html

Mailing List Third Party Advisory
Bugs
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1867717

Exploit Third Party Advisory
Ubuntu Security
https://usn.ubuntu.com/4318-1/

Third Party Advisory
Ubuntu Security
https://usn.ubuntu.com/usn/usn-4318-1

Third Party Advisory
Openwall
https://www.openwall.com/lists/oss-security/2020/04/06/2

Mailing List Third Party Advisory

Details

CVE ID CVE-2020-8834

Severity Medium

CVSS score 6.5 / 10

CVSS version 3.1

Published 2020-04-09

Modified 2024-11-21

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2020-8834?

CVE-2020-8834 is a Medium severity Linux kernel vulnerability with a CVSS score of 6.5 out of 10 . CVE-2020-8834 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2020-8834?

CVE-2020-8834 has a CVSS score of 6.5 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:C/C:N/I:N/A:H.
Is there a patch available for CVE-2020-8834?

No patch is currently available for CVE-2020-8834. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2020-8834 actively exploited?

No — CVE-2020-8834 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.