How severe is CVE-2021-4238?

CVE-2021-4238 has a CVSS 3.x base score of 9.1, 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 none, and availability high.

Is CVE-2021-4238 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4238?

CVE-2021-4238 affects Goutils Project Goutils. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4238?

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-2021-4238 published?

CVE-2021-4238 was published on 2022-12-27 and last updated on 2026-06-17.

CVE-2021-4238

CVE-2021-4238 is a critical-severity vulnerability in Goutils Project Goutils with a CVSS 3.x base score of 9.1. 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-331.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-331
Affected product: Goutils Project Goutils
Published: 2022-12-27
Last modified: 2026-06-17

Description

Randomly-generated alphanumeric strings contain significantly less entropy than expected. The RandomAlphaNumeric and CryptoRandomAlphaNumeric functions always return strings containing at least one digit from 0 to 9. This significantly reduces the amount of entropy in short strings generated by these functions.

Frequently asked questions

What is CVE-2021-4238?: Randomly-generated alphanumeric strings contain significantly less entropy than expected. The RandomAlphaNumeric and CryptoRandomAlphaNumeric functions always return strings containing at least one digit from 0 to 9. This significantly reduces the amount of entropy in short strings generated by these functions.
How severe is CVE-2021-4238?: CVE-2021-4238 has a CVSS 3.x base score of 9.1, 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 none, and availability high.
Is CVE-2021-4238 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4238?: CVE-2021-4238 affects Goutils Project Goutils. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4238?: 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-2021-4238 published?: CVE-2021-4238 was published on 2022-12-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:goutils_project:goutils:*:*:*:*:*:go:*:*

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