Vulnerability identifier: #VU70582

Vulnerability 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-2022-42326

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Xen
Server applications / Virtualization software

Vendor: Xen Project

Description

The vulnerability allows a malicious guest to perform a denial of service (DoS) attack.

The vulnerability exists due to missing control over the number of created nodes in Xenstore. A malicious guest can consume all available memory resources by created an unlimited number of nodes.

The vulnerability affects the C variant of Xenstore (e.g. xenstored and xenstore-stubdom).

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Xen: All versions

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External links
http://xenbits.xenproject.org/xsa/advisory-421.txt
http://xenbits.xen.org/xsa/advisory-421.html
http://www.openwall.com/lists/oss-security/2022/11/01/11
http://www.debian.org/security/2022/dsa-5272
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZLI2NPNEH7CNJO3VZGQNOI4M4EWLNKPZ/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/YZVXG7OOOXCX6VIPEMLFDPIPUTFAYWPE/
http://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/YTMITQBGC23MSDHUCAPCVGLMVXIBXQTQ/

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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.