#VU92418 Allocation of resources without limits or throttling in Linux kernel - CVE-2021-26931

Vulnerability identifier: #VU92418

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-26931

CWE-ID: CWE-770

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 (DoS) attack.

The vulnerability exists due to allocation of resources without limits or throttling error within the scsiback_gnttab_data_map_batch() function in drivers/xen/xen-scsiback.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's repository.

Vulnerable software versions

Linux kernel: All versions

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External links
https://xenbits.xen.org/xsa/advisory-362.html
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
https://security.netapp.com/advisory/ntap-20210326-0001/
https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2XQR52ICKRK3GC4HDWLMWF2U55YGAR63/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GWQWPWYZRXVFJI5M3VCM72X27IB7CKOB/
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7c77474b2d22176d2bfb592ec74e0f2cb71352c9
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5a264285ed1cd32e26d9de4f3c8c6855e467fd63
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3194a1746e8aabe86075fd3c5e7cf1f4632d7f16

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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.