How severe is CVE-2021-21506?

CVE-2021-21506 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-21506 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-2021-21506?

CVE-2021-21506 primarily affects Dell Emc Powerscale Onefs. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21506?

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-2021-21506 published?

CVE-2021-21506 was published on 2021-03-08 and last updated on 2026-06-17.

CVE-2021-21506

CVE-2021-21506 is a high-severity vulnerability in Dell Emc Powerscale Onefs with a CVSS 3.x base score of 8.8. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Dell Emc Powerscale Onefs
Published: 2021-03-08
Last modified: 2026-06-17

Description

PowerScale OneFS 8.1.2,8.2.2 and 9.1.0 contains an improper input sanitization issue in its API handler. An un-authtenticated with ISI_PRIV_SYS_SUPPORT and ISI_PRIV_LOGIN_PAPI privileges could potentially exploit this vulnerability, leading to potential privileges escalation.

Frequently asked questions

What is CVE-2021-21506?: PowerScale OneFS 8.1.2,8.2.2 and 9.1.0 contains an improper input sanitization issue in its API handler. An un-authtenticated with ISI_PRIV_SYS_SUPPORT and ISI_PRIV_LOGIN_PAPI privileges could potentially exploit this vulnerability, leading to potential privileges escalation.
How severe is CVE-2021-21506?: CVE-2021-21506 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-21506 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-2021-21506?: CVE-2021-21506 primarily affects Dell Emc Powerscale Onefs. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21506?: 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-2021-21506 published?: CVE-2021-21506 was published on 2021-03-08 and last updated on 2026-06-17.

References

https://www.dell.com/support/kbdoc/000183717

Affected products (3)

cpe:2.3:o:dell:emc_powerscale_onefs:8.1.2:*:*:*:*:*:*:*
cpe:2.3:o:dell:emc_powerscale_onefs:8.2.2:*:*:*:*:*:*:*
cpe:2.3:o:dell:emc_powerscale_onefs:9.1.0:*:*:*:*:*:*:*

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