How severe is CVE-2021-23420?

CVE-2021-23420 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2021-23420 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23420?

CVE-2021-23420 affects Codeception. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23420?

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-2021-23420 published?

CVE-2021-23420 was published on 2021-08-11 and last updated on 2026-06-17.

CVE-2021-23420

CVE-2021-23420 is a high-severity vulnerability in Codeception with a CVSS 3.x base score of 7.7. 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-502.

Key facts

Severity: High (CVSS 3.x base score 7.7)
CVSS v2: 10.0
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Codeception
Published: 2021-08-11
Last modified: 2026-06-17

Description

This affects the package codeception/codeception from 4.0.0 and before 4.1.22, before 3.1.3. The RunProcess class can be leveraged as a gadget to run arbitrary commands on a system that is deserializing user input without validation.

Frequently asked questions

What is CVE-2021-23420?: This affects the package codeception/codeception from 4.0.0 and before 4.1.22, before 3.1.3. The RunProcess class can be leveraged as a gadget to run arbitrary commands on a system that is deserializing user input without validation.
How severe is CVE-2021-23420?: CVE-2021-23420 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2021-23420 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23420?: CVE-2021-23420 affects Codeception. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23420?: 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-2021-23420 published?: CVE-2021-23420 was published on 2021-08-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:codeception:codeception:*:*:*:*:*:*:*:*

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