How severe is CVE-2021-42558?

CVE-2021-42558 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-42558 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42558?

CVE-2021-42558 affects Mitre Caldera. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42558?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-42558 published?

CVE-2021-42558 was published on 2022-01-12 and last updated on 2026-06-17.

CVE-2021-42558

CVE-2021-42558 is a medium-severity vulnerability in Mitre Caldera with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mitre Caldera
Published: 2022-01-12
Last modified: 2026-06-17

Description

An issue was discovered in CALDERA 2.8.1. It contains multiple reflected, stored, and self XSS vulnerabilities that may be exploited by authenticated and unauthenticated attackers.

Frequently asked questions

What is CVE-2021-42558?: An issue was discovered in CALDERA 2.8.1. It contains multiple reflected, stored, and self XSS vulnerabilities that may be exploited by authenticated and unauthenticated attackers.
How severe is CVE-2021-42558?: CVE-2021-42558 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-42558 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42558?: CVE-2021-42558 affects Mitre Caldera. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42558?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42558 published?: CVE-2021-42558 was published on 2022-01-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mitre:caldera:*:*:*:*:*:*:*:*

More vulnerabilities in Mitre Caldera

CVE-2021-42559 — High (CVSS 8.8): An issue was discovered in CALDERA 2.8.1. It contains multiple startup "requirements" that execute commands when…
CVE-2021-42561 — High (CVSS 8.8): An issue was discovered in CALDERA 2.8.1. When activated, the Human plugin passes the unsanitized name parameter to a…
CVE-2021-42560 — High (CVSS 8.8): An issue was discovered in CALDERA 2.9.0. The Debrief plugin receives base64 encoded "SVG" parameters when generating a…
CVE-2020-19907 — High (CVSS 8.8): A command injection vulnerability in the sandcat plugin of Caldera 2.3.1 and earlier allows authenticated attackers to…
CVE-2021-42562 — High (CVSS 8.1): An issue was discovered in CALDERA 2.8.1. It does not properly segregate user privileges, resulting in non-admin users…
CVE-2022-40606 — Medium (CVSS 6.1): MITRE CALDERA before 4.1.0 allows XSS in the Operations tab and/or Debrief plugin via a crafted operation name, a…

All CVEs affecting Mitre Caldera →

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