#VU68718 Use-after-free in expat - CVE-2022-43680

Vulnerability identifier: #VU68718

Vulnerability 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

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
expat
Universal components / Libraries / Libraries used by multiple products

Vendor: libexpat.org

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
Install updates from vendor's website.

Vulnerable software versions

expat: 1.95.0 - 2.4.9

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External links
https://github.com/libexpat/libexpat/pull/650
https://github.com/libexpat/libexpat/pull/616
https://github.com/libexpat/libexpat/issues/649

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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.