#VU72631 Stack-based buffer overflow in Lua - CVE-2021-43519

Vulnerability identifier: #VU72631

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-2021-43519

CWE-ID: CWE-121

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 boundary error within the lua_resume() function of ldo.c. A remote attacker can pass a specially crafted script file to he application, trigger a stack-based buffer overflow and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Lua: 5.1 - 5.3.4

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External links
https://lua-users.org/lists/lua-l/2021-11/msg00015.html
https://lua-users.org/lists/lua-l/2021-10/msg00123.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/C7XHFYHGSZKL53VCLSJSAJ6VMFGAIXKO/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/P3EMGAQ5Y6GXJLY4K5DUOOEQT4MZ4J4F/

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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.