#VU75704 Type Confusion in Lua - CVE-2021-44647

Vulnerability identifier: #VU75704

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-44647

CWE-ID: CWE-843

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Lua
Universal components / Libraries / Scripting languages

Vendor: Lua

Description

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

The vulnerability exists due to a type confusion error within the funcnamefromcode() function in ldebug.c. A remote attacker can pass specially crafted data to the application, trigger a type confusion error and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Lua: 5.4.0 - 5.4.3

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External links
https://lua-users.org/lists/lua-l/2021-11/msg00204.html
https://lua-users.org/lists/lua-l/2021-11/msg00195.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/P3EMGAQ5Y6GXJLY4K5DUOOEQT4MZ4J4F/
https://access.redhat.com/security/cve/cve-2021-44647

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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.