MEDIUM

CVE-2021-43519

CVSS v3

5.5

MEDIUM

EPSS Score

1.2 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

luaBitnamifrom 5.1.0 · fixed in 5.3.5
luaAlmaLinux:9all versions · fixed in 5.4.4-2.el9_1and 2 other packages

Vendor advisories

CVE-2021-43519 Red Hat Product Security116 products fixed · 6 known affected
lua: stack overflow in lua_resume of ldo.c allows a DoS via a crafted script file
lua-devel as a component of Red Hat Enterprise Linux 6 · lua-static as a component of Red Hat Enterprise Linux 6 · lua.src as a component of Red Hat Enterprise Linux 6
RHSA-2023:1211 Red Hat Product Security58 products fixed
Red Hat Security Advisory: lua security update
RHSA-2023:0957 Red Hat Product Security58 products fixed
Red Hat Security Advisory: lua security update

Full record on NVD

Description

Stack overflow in lua_resume of ldo.c in Lua Interpreter 5.1.0~5.4.4 allows attackers to perform a Denial of Service via a crafted script file.

Technical details

Published: 2021-11-09

Frequently asked questions

What is CVE-2021-43519?

Stack overflow in lua_resume of ldo.c in Lua Interpreter 5.1.0~5.4.4 allows attackers to perform a Denial of Service via a crafted script file.

Is CVE-2021-43519 actively exploited?

Active exploitation of CVE-2021-43519 has not been confirmed. Its EPSS score was 1.2% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-43519?

CVE-2021-43519 has a CVSS v3 base score of 5.5 (MEDIUM severity).

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