How severe is CVE-2021-34993?

CVE-2021-34993 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-2021-34993 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34993?

CVE-2021-34993 affects Commvault Commcell. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34993?

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-2021-34993 published?

CVE-2021-34993 was published on 2022-01-13 and last updated on 2026-06-17.

CVE-2021-34993

CVE-2021-34993 is a critical-severity vulnerability in Commvault Commcell 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 5% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Commvault Commcell
Published: 2022-01-13
Last modified: 2026-06-17

Description

This vulnerability allows remote attackers to bypass authentication on affected installations of Commvault CommCell 11.22.22. Authentication is not required to exploit this vulnerability. The specific flaw exists within the CVSearchService service. The issue results from the lack of proper validation prior to authentication. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-13706.

Frequently asked questions

What is CVE-2021-34993?: This vulnerability allows remote attackers to bypass authentication on affected installations of Commvault CommCell 11.22.22. Authentication is not required to exploit this vulnerability. The specific flaw exists within the CVSearchService service. The issue results from the lack of proper validation prior to authentication. An attacker can leverage this vulnerability to bypass authentication on the system. Was ZDI-CAN-13706.
How severe is CVE-2021-34993?: CVE-2021-34993 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-2021-34993 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34993?: CVE-2021-34993 affects Commvault Commcell. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34993?: 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-2021-34993 published?: CVE-2021-34993 was published on 2022-01-13 and last updated on 2026-06-17.

References

https://www.zerodayinitiative.com/advisories/ZDI-21-1328/

Affected products (1)

cpe:2.3:a:commvault:commcell:11.22.22:*:*:*:*:*:*:*

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