How severe is CVE-2021-44964?

CVE-2021-44964 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-44964 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-44964?

CVE-2021-44964 affects Lua. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-44964?

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

When was CVE-2021-44964 published?

CVE-2021-44964 was published on 2022-03-14 and last updated on 2026-06-17.

CVE-2021-44964

CVE-2021-44964 is a medium-severity vulnerability in Lua with a CVSS 3.x base score of 6.3. 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-416.

Key facts

Severity: Medium (CVSS 3.x base score 6.3)
CVSS v2: 4.3
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Lua
Published: 2022-03-14
Last modified: 2026-06-17

Description

Use after free in garbage collector and finalizer of lgc.c in Lua interpreter 5.4.0~5.4.3 allows attackers to perform Sandbox Escape via a crafted script file.

Frequently asked questions

What is CVE-2021-44964?: Use after free in garbage collector and finalizer of lgc.c in Lua interpreter 5.4.0~5.4.3 allows attackers to perform Sandbox Escape via a crafted script file.
How severe is CVE-2021-44964?: CVE-2021-44964 has a CVSS 3.x base score of 6.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-44964 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-44964?: CVE-2021-44964 affects Lua. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-44964?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-44964 published?: CVE-2021-44964 was published on 2022-03-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:lua:lua:*:*:*:*:*:*:*:*

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