How severe is CVE-2021-44647?

CVE-2021-44647 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-44647 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44647?

CVE-2021-44647 primarily affects Lua. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-44647?

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

When was CVE-2021-44647 published?

CVE-2021-44647 was published on 2022-01-11 and last updated on 2026-06-17.

CVE-2021-44647

CVE-2021-44647 is a medium-severity vulnerability in Lua with a CVSS 3.x base score of 5.5. 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-843.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-843
Affected product: Lua
Published: 2022-01-11
Last modified: 2026-06-17

Description

Lua v5.4.3 and above are affected by SEGV by type confusion in funcnamefromcode function in ldebug.c which can cause a local denial of service.

Frequently asked questions

What is CVE-2021-44647?: Lua v5.4.3 and above are affected by SEGV by type confusion in funcnamefromcode function in ldebug.c which can cause a local denial of service.
How severe is CVE-2021-44647?: CVE-2021-44647 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-44647 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44647?: CVE-2021-44647 primarily affects Lua. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-44647?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-44647 published?: CVE-2021-44647 was published on 2022-01-11 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:lua:lua:5.4.3:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

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