How severe is CVE-2020-24370?

CVE-2020-24370 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2020-24370 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-24370?

CVE-2020-24370 primarily affects Lua. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-24370?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-24370 published?

CVE-2020-24370 was published on 2020-08-17 and last updated on 2026-06-17.

CVE-2020-24370

CVE-2020-24370 is a medium-severity vulnerability in Lua with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-191.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 4% (89th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Lua
Published: 2020-08-17
Last modified: 2026-06-17

Description

ldebug.c in Lua 5.4.0 allows a negation overflow and segmentation fault in getlocal and setlocal, as demonstrated by getlocal(3,2^31).

Frequently asked questions

What is CVE-2020-24370?: ldebug.c in Lua 5.4.0 allows a negation overflow and segmentation fault in getlocal and setlocal, as demonstrated by getlocal(3,2^31).
How severe is CVE-2020-24370?: CVE-2020-24370 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2020-24370 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-24370?: CVE-2020-24370 primarily affects Lua. In total, 20 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-24370?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-24370 published?: CVE-2020-24370 was published on 2020-08-17 and last updated on 2026-06-17.

References

Affected products (20)

cpe:2.3:a:lua:lua:5.2.0:-:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.2.0:alpha:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.2.0:beta:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.2.1:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.2.2:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.2.3:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.0:-:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.0:alpha:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.0:beta:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.1:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.2:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.3:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.4:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.3.5:*:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.4.0:-:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.4.0:alpha:*:*:*:*:*:*
cpe:2.3:a:lua:lua:5.4.0:beta:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

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