How severe is CVE-2021-41166?

CVE-2021-41166 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-41166 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41166?

CVE-2021-41166 affects Nextcloud. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41166?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-41166 published?

CVE-2021-41166 was published on 2022-01-26 and last updated on 2026-06-17.

CVE-2021-41166

CVE-2021-41166 is a medium-severity vulnerability in Nextcloud with a CVSS 3.x base score of 4.3. 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-276.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-276
Affected product: Nextcloud
Published: 2022-01-26
Last modified: 2026-06-17

Description

The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. An issue in versions prior to 3.17.1 may lead to sensitive information disclosure. An unauthorized app that does not have the otherwise required `MANAGE_DOCUMENTS` permission may view image thumbnails for images it does not have permission to view. Version 3.17.1 contains a patch. There are no known workarounds.

Frequently asked questions

What is CVE-2021-41166?: The Nextcloud Android app is the Android client for Nextcloud, a self-hosted productivity platform. An issue in versions prior to 3.17.1 may lead to sensitive information disclosure. An unauthorized app that does not have the otherwise required `MANAGE_DOCUMENTS` permission may view image thumbnails for images it does not have permission to view. Version 3.17.1 contains a patch. There are no known workarounds.
How severe is CVE-2021-41166?: CVE-2021-41166 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-41166 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41166?: CVE-2021-41166 affects Nextcloud. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41166?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-41166 published?: CVE-2021-41166 was published on 2022-01-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:android:*:*

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