How severe is CVE-2021-23567?

CVE-2021-23567 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-2021-23567 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23567?

CVE-2021-23567 primarily affects Colors.js Project Colors.js. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-23567?

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-2021-23567 published?

CVE-2021-23567 was published on 2022-01-14 and last updated on 2026-06-17.

CVE-2021-23567

CVE-2021-23567 is a high-severity vulnerability in Colors.js Project Colors.js 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-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Colors.js Project Colors.js
Published: 2022-01-14
Last modified: 2026-06-17

Description

The package colors after 1.4.0 are vulnerable to Denial of Service (DoS) that was introduced through an infinite loop in the americanFlag module. Unfortunately this appears to have been a purposeful attempt by a maintainer of colors to make the package unusable, other maintainers' controls over this package appear to have been revoked in an attempt to prevent them from fixing the issue. Vulnerable Code js for (let i = 666; i < Infinity; i++;) { Alternative Remediation Suggested * Pin dependancy to 1.4.0

Frequently asked questions

What is CVE-2021-23567?: The package colors after 1.4.0 are vulnerable to Denial of Service (DoS) that was introduced through an infinite loop in the americanFlag module. Unfortunately this appears to have been a purposeful attempt by a maintainer of colors to make the package unusable, other maintainers' controls over this package appear to have been revoked in an attempt to prevent them from fixing the issue. Vulnerable Code js for (let i = 666; i < Infinity; i++;) { Alternative Remediation Suggested * Pin dependancy to 1.4.0
How severe is CVE-2021-23567?: CVE-2021-23567 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-2021-23567 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23567?: CVE-2021-23567 primarily affects Colors.js Project Colors.js. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-23567?: 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-2021-23567 published?: CVE-2021-23567 was published on 2022-01-14 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:colors.js_project:colors.js:1.4.1:*:*:*:*:node.js:*:*
cpe:2.3:a:colors.js_project:colors.js:1.4.44-liberty-2:*:*:*:*:node.js:*:*

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