CVE-2021-34995

CVE-2021-34995 is a high-severity vulnerability in Commvault Commcell with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 69% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-434.

Key facts

Description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Commvault CommCell 11.22.22. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the DownloadCenterUploadHandler class. The issue results from the lack of proper validation of user-supplied data, which can allow the upload of arbitrary files. An attacker can leverage this vulnerability to execute code in the context of NETWORK SERVICE. Was ZDI-CAN-13756.

Frequently asked questions

What is CVE-2021-34995?
This vulnerability allows remote attackers to execute arbitrary code on affected installations of Commvault CommCell 11.22.22. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the DownloadCenterUploadHandler class. The issue results from the lack of proper validation of user-supplied data, which can allow the upload of arbitrary files. An attacker can leverage this vulnerability to execute code in the context of NETWORK SERVICE. Was ZDI-CAN-13756.
How severe is CVE-2021-34995?
CVE-2021-34995 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-2021-34995 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 69% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34995?
CVE-2021-34995 affects Commvault Commcell. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34995?
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-2021-34995 published?
CVE-2021-34995 was published on 2022-01-13 and last updated on 2026-06-17.

References

Affected products (1)

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