Ubuntu update for expat

Published: 2022-11-23

Risk	Medium
Patch available	YES
Number of vulnerabilities	1
CVE-ID	CVE-2022-43680
CWE-ID	CWE-416
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	Ubuntu Operating systems & Components / Operating system lib64expat1 (Ubuntu package) Operating systems & Components / Operating system package or component libexpat1 (Ubuntu package) Operating systems & Components / Operating system package or component expat (Ubuntu package) Operating systems & Components / Operating system package or component
Vendor	Canonical Ltd.

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Use-after-free

EUVDB-ID: #VU68718

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-43680

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

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

The vulnerability exists due to a use-after-free error caused by overeager destruction of a shared DTD in XML_ExternalEntityParserCreate. A remote attacker can trigger a use-after-free error and perform a denial of service (DoS) attack.

Mitigation

Update the affected package expat to the latest version.

Vulnerable software versions

Ubuntu: 16.04 - 22.10

lib64expat1 (Ubuntu package): before Ubuntu Pro (Infra-only)

libexpat1 (Ubuntu package): before Ubuntu Pro (Infra-only)

expat (Ubuntu package): before Ubuntu Pro (Infra-only)

External links

http://ubuntu.com/security/notices/USN-5638-3

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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