How severe is CVE-2021-22891?

CVE-2021-22891 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-2021-22891 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22891?

CVE-2021-22891 affects Citrix Sharefile Storagezones Controller. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-22891?

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-2021-22891 published?

CVE-2021-22891 was published on 2021-05-27 and last updated on 2026-06-17.

CVE-2021-22891

CVE-2021-22891 is a critical-severity vulnerability in Citrix Sharefile Storagezones Controller 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-862.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-862
Affected product: Citrix Sharefile Storagezones Controller
Published: 2021-05-27
Last modified: 2026-06-17

Description

A missing authorization vulnerability exists in Citrix ShareFile Storage Zones Controller before 5.7.3, 5.8.3, 5.9.3, 5.10.1 and 5.11.18 may allow unauthenticated remote compromise of the Storage Zones Controller.

Frequently asked questions

What is CVE-2021-22891?: A missing authorization vulnerability exists in Citrix ShareFile Storage Zones Controller before 5.7.3, 5.8.3, 5.9.3, 5.10.1 and 5.11.18 may allow unauthenticated remote compromise of the Storage Zones Controller.
How severe is CVE-2021-22891?: CVE-2021-22891 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-2021-22891 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22891?: CVE-2021-22891 affects Citrix Sharefile Storagezones Controller. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-22891?: 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-2021-22891 published?: CVE-2021-22891 was published on 2021-05-27 and last updated on 2026-06-17.

References

https://support.citrix.com/article/CTX310780

Affected products (1)

cpe:2.3:a:citrix:sharefile_storagezones_controller:*:*:*:*:*:*:*:*

More vulnerabilities in Citrix Sharefile Storagezones Controller

CVE-2021-22941 — Critical (CVSS 9.8): Improper Access Control in Citrix ShareFile storage zones controller before 5.11.20 may allow an unauthenticated…
CVE-2021-22932 — High (CVSS 7.5): An issue has been identified in the CTX269106 mitigation tool for Citrix ShareFile storage zones controller which…
CVE-2020-8983 — High (CVSS 7.5): An arbitrary file write issue exists in all versions of Citrix ShareFile StorageZones (aka storage zones) Controller,…
CVE-2020-8982 — High (CVSS 7.5): An unauthenticated arbitrary file read issue exists in all versions of Citrix ShareFile StorageZones (aka storage…
CVE-2020-7473 — High (CVSS 7.5): In certain situations, all versions of Citrix ShareFile StorageZones (aka storage zones) Controller, including the most…
CVE-2018-16969 — Medium (CVSS 4.3): Citrix ShareFile StorageZones Controller before 5.4.2 has Information Exposure Through an Error Message.

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