How severe is CVE-2021-23449?

CVE-2021-23449 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-23449 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23449?

CVE-2021-23449 affects Vm2 Project Vm2. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23449?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-23449 published?

CVE-2021-23449 was published on 2021-10-18 and last updated on 2026-06-17.

CVE-2021-23449

CVE-2021-23449 is a critical-severity vulnerability in Vm2 Project Vm2 with a CVSS 3.x base score of 9.8. 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-1321.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1321
Affected product: Vm2 Project Vm2
Published: 2021-10-18
Last modified: 2026-06-17

Description

This affects the package vm2 before 3.9.4 via a Prototype Pollution attack vector, which can lead to execution of arbitrary code on the host machine.

Frequently asked questions

What is CVE-2021-23449?: This affects the package vm2 before 3.9.4 via a Prototype Pollution attack vector, which can lead to execution of arbitrary code on the host machine.
How severe is CVE-2021-23449?: CVE-2021-23449 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-23449 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23449?: CVE-2021-23449 affects Vm2 Project Vm2. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23449?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-23449 published?: CVE-2021-23449 was published on 2021-10-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:vm2_project:vm2:*:*:*:*:*:node.js:*:*

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