#VU48558 Memory corruption in Lua - CVE-2020-15945

Vulnerability identifier: #VU48558

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-2020-15945

CWE-ID: CWE-119

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 segmentation fault in changedline in ldebug.c (e.g., when called by luaG_traceexec) because it incorrectly expects that an oldpc value is always updated upon a return of the flow of control to a function. A remote attacker can pass specially crafted data to the application and crash it.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Lua: 5.2.0 - 5.4.0

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External links
https://lua-users.org/lists/lua-l/2020-07/msg00123.html
https://github.com/lua/lua/commit/a2195644d89812e5b157ce7bac35543e06db05e3

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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.