PT-2021-23858 · Lua+6 · Lua+6

김지회 · Published 2019-08-09 · Updated 2025-08-03 · CVE-2021-43519

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Lua Interpreter versions 5.1.0 through 5.4.4

Description The issue is related to a stack overflow in the lua resume function of ldo.c in the Lua Interpreter. This can allow attackers to perform a Denial of Service via a crafted script file. The vulnerability is associated with a buffer overflow in the stack. Exploitation of the vulnerability can enable an attacker to cause a denial of service.

Recommendations For Lua Interpreter versions 5.1.0 through 5.4.4, consider disabling the lua resume function as a temporary workaround until a patch is available. Restrict the execution of crafted script files to minimize the risk of exploitation. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

DoS

Uncontrolled Recursion

Stack Overflow

Weakness Enumeration

CWE-674

CWE-121

Related Identifiers

ALSA-2023:0957

ALT-PU-2019-2423

ALT-PU-2019-2424

AZL-41261

AZL-41445

AZL-41574

AZL-41866

AZL-6672

BDU:2025-01458

BIT-LUA-2021-43519

CVE-2021-43519

OPENSUSE-SU-2024:12156-1

OPENSUSE-SU-2025:15401-1

RHSA-2023:0957

RHSA-2023:1211

RHSA-2023_0957

RLSA-2023:0957

Affected Products

Alt Linux

Almalinux

Debian

Lua

Red Hat

Red Os

Rocky Linux

References · 47

• 🔥 https://github.com/Lua-Project/cve-analysis/blob/a43c9ccd00274b31fa2f24c6c8f20ce36655682d/CVE-2019-6706.pdf · Exploit
• 🔥 http://lua-users.org/lists/lua-l/2021-10/msg00123.html · Exploit
• https://osv.dev/vulnerability/CVE-2021-43519 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-43519 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-43519 · Security Note
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/P3EMGAQ5Y6GXJLY4K5DUOOEQT4MZ4J4F · Vendor Advisory
• https://errata.rockylinux.org/RLSA-2023:0957 · Vendor Advisory
• https://osv.dev/vulnerability/AZL-41261 · Vendor Advisory
• https://osv.dev/vulnerability/AZL-41445 · Vendor Advisory
• https://errata.almalinux.org/9/ALSA-2023-0957.html · Vendor Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/C7XHFYHGSZKL53VCLSJSAJ6VMFGAIXKO · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2021-43519 · Security Note
• http://lua-users.org/lists/lua-l/2021-11/msg00015.html · Vendor Advisory
• https://osv.dev/vulnerability/AZL-41866 · Vendor Advisory
• https://osv.dev/vulnerability/AZL-41574 · Vendor Advisory