How severe is CVE-2021-23391?

CVE-2021-23391 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.

Is CVE-2021-23391 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23391?

CVE-2021-23391 affects Calipso Project Calipso. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23391?

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-2021-23391 published?

CVE-2021-23391 was published on 2021-06-07 and last updated on 2026-06-17.

CVE-2021-23391

CVE-2021-23391 is a high-severity vulnerability in Calipso Project Calipso with a CVSS 3.x base score of 7.3. 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-22.

Key facts

Severity: High (CVSS 3.x base score 7.3)
CVSS v2: 3.6
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Calipso Project Calipso
Published: 2021-06-07
Last modified: 2026-06-17

Description

This affects all versions of package calipso. It is possible for a malicious module to overwrite files on an arbitrary file system through the module install functionality.

Frequently asked questions

What is CVE-2021-23391?: This affects all versions of package calipso. It is possible for a malicious module to overwrite files on an arbitrary file system through the module install functionality.
How severe is CVE-2021-23391?: CVE-2021-23391 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability low.
Is CVE-2021-23391 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23391?: CVE-2021-23391 affects Calipso Project Calipso. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23391?: 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-2021-23391 published?: CVE-2021-23391 was published on 2021-06-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:calipso_project:calipso:*:*:*:*:*:*:*:*

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