How severe is CVE-2021-20850?

CVE-2021-20850 has a CVSS 3.x base score of 9.8, 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 high, and availability high.

Is CVE-2021-20850 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20850?

CVE-2021-20850 affects Alfasado Powercms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20850?

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-2021-20850 published?

CVE-2021-20850 was published on 2021-11-24 and last updated on 2026-06-17.

CVE-2021-20850

CVE-2021-20850 is a critical-severity vulnerability in Alfasado Powercms with a CVSS 3.x base score of 9.8. 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-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Alfasado Powercms
Published: 2021-11-24
Last modified: 2026-06-17

Description

PowerCMS XMLRPC API of PowerCMS 5.19 and earlier, PowerCMS 4.49 and earlier, PowerCMS 3.295 and earlier, and PowerCMS 2 Series (End-of-Life, EOL) allows a remote attacker to execute an arbitrary OS command via unspecified vectors.

Frequently asked questions

What is CVE-2021-20850?: PowerCMS XMLRPC API of PowerCMS 5.19 and earlier, PowerCMS 4.49 and earlier, PowerCMS 3.295 and earlier, and PowerCMS 2 Series (End-of-Life, EOL) allows a remote attacker to execute an arbitrary OS command via unspecified vectors.
How severe is CVE-2021-20850?: CVE-2021-20850 has a CVSS 3.x base score of 9.8, 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 high, and availability high.
Is CVE-2021-20850 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20850?: CVE-2021-20850 affects Alfasado Powercms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20850?: 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-2021-20850 published?: CVE-2021-20850 was published on 2021-11-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:alfasado:powercms:*:*:*:*:*:*:*:*

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