Resource exhaustion in xen (Alpine package)

1) Resource exhaustion

EUVDB-ID: #VU46984

Risk: Medium

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-25601

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

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

The vulnerability exists due to improper management of internal resources within the application, as the FIFO event channel model allows guests to have a large number of event channels active at a time.  Closing all of these when resetting all event channels or when cleaning up after the guest may take extended periods of time.  So far there was no arrangement for preemption at suitable intervals, allowing a CPU to spend an almost unbounded amount of time in the processing of these operations. A remote user can consume all available CPU resources and perform a denial of service (DoS) attack of the entire host system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

xen (Alpine package): 4.10.1-r0 - 4.14.0-r0

External links

http://git.alpinelinux.org/aports/commit/?id=f48590ae54ca9e0c3bf6b3fae3e6b065f14223e3

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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