Error handling issues in blkback's grant mapping in Xen

1) Resource management error

EUVDB-ID: #VU51587

Risk: Medium

CVSSv3.1: 4.3 [CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-26930

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

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

The vulnerability exists due to improper management of internal resources when processing service requests to the PV backend within drivers/block/xen-blkback/blkback.c driver in Xen. A local user on the guest OS can perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Linux kernel: 5.10.16

External links

http://xenbits.xen.org/xsa/advisory-365.html
http://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2XQR52ICKRK3GC4HDWLMWF2U55YGAR63/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GWQWPWYZRXVFJI5M3VCM72X27IB7CKOB/

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

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