Vulnerability identifier: #VU63921

Vulnerability risk: Low

CVSSv3.1: 4.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-43056

CWE-ID: CWE-252

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to perform a denial of service attack.

The vulnerability exists due to an arch/powerpc/kvm/book3s_hv_rmhandlers.S implementation error when handling SRR1 register values. A local user can perform a denial of service attack, when the host is running on Power8.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
http://git.kernel.org/linus/cdeb5d7d890e14f3b70e8087e745c4a6a7d9f337
http://lore.kernel.org/linuxppc-dev/87pmrtbbdt.fsf@mpe.ellerman.id.au/T/#u
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14.15
http://www.openwall.com/lists/oss-security/2021/10/28/1
http://bugzilla.redhat.com/show_bug.cgi?id=2017073

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.