How severe is CVE-2021-41167?

CVE-2021-41167 has a CVSS 3.x base score of 7.5, rated high 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 high.

Is CVE-2021-41167 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41167?

CVE-2021-41167 affects Modern-async Project Modern-async. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41167?

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

When was CVE-2021-41167 published?

CVE-2021-41167 was published on 2021-10-20 and last updated on 2026-06-17.

CVE-2021-41167

CVE-2021-41167 is a high-severity vulnerability in Modern-async Project Modern-async with a CVSS 3.x base score of 7.5. 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Modern-async Project Modern-async
Published: 2021-10-20
Last modified: 2026-06-17

Description

modern-async is an open source JavaScript tooling library for asynchronous operations using async/await and promises. In affected versions a bug affecting two of the functions in this library: forEachSeries and forEachLimit. They should limit the concurrency of some actions but, in practice, they don't. Any code calling these functions will be written thinking they would limit the concurrency but they won't. This could lead to potential security issues in other projects. The problem has been patched in 1.0.4. There is no workaround.

Frequently asked questions

What is CVE-2021-41167?: modern-async is an open source JavaScript tooling library for asynchronous operations using async/await and promises. In affected versions a bug affecting two of the functions in this library: forEachSeries and forEachLimit. They should limit the concurrency of some actions but, in practice, they don't. Any code calling these functions will be written thinking they would limit the concurrency but they won't. This could lead to potential security issues in other projects. The problem has been patched in 1.0.4. There is no workaround.
How severe is CVE-2021-41167?: CVE-2021-41167 has a CVSS 3.x base score of 7.5, rated high 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 high.
Is CVE-2021-41167 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41167?: CVE-2021-41167 affects Modern-async Project Modern-async. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41167?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-41167 published?: CVE-2021-41167 was published on 2021-10-20 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:modern-async_project:modern-async:*:*:*:*:*:node.js:*:*

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