Ubuntu update for expat

1) Use-after-free

EUVDB-ID: #VU68718

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

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)

CPE2.3

• cpe:2.3:o:canonical:ubuntu:16.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:18.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:20.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:22.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:22.10:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:lib64expat1_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:o:canonical:libexpat1_ubuntu_package:*:*:*:*:*:ubuntu:*:*
• cpe:2.3:o:canonical:expat_ubuntu_package:*:*:*:*:*:ubuntu:*:*

External links

https://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.