CVE-2021-22915: Critical severity Nextcloud Server vulnerability

Published Jun 11, 2021
·
Updated

Nextcloud server before 19.0.11, 20.0.10, 21.0.2 is vulnerable to brute force attacks due to lack of inclusion of IPv6 subnets in rate-limiting considerations. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.

Affected Software

5 affected components
Nextcloud Server<19.0.11
Nextcloud Server>=20.0.0<20.0.10
Nextcloud Server>=21.0.0<21.0.2
fedoraproject fedora=33
fedoraproject fedora=34

Event History

Jun 11, 2021
CVE Published
via MITRE·03:49 PM
Data Sourced
via MITRE·03:49 PM
DescriptionWeakness

Frequently Asked Questions

1

What is the severity of CVE-2021-22915?

CVE-2021-22915 is considered a moderate severity vulnerability due to its potential for allowing brute-force attacks.

2

How do I fix CVE-2021-22915?

To fix CVE-2021-22915, upgrade to Nextcloud server version 19.0.11, 20.0.10, or 21.0.2 or later.

3

What types of attacks are associated with CVE-2021-22915?

CVE-2021-22915 is associated with brute force attacks that exploit the lack of IPv6 subnet rate-limiting.

4

Which versions of Nextcloud are affected by CVE-2021-22915?

CVE-2021-22915 affects Nextcloud server versions prior to 19.0.11, 20.0.10, and 21.0.2.

5

Is CVE-2021-22915 specific to IPv6 users?

Yes, CVE-2021-22915 specifically impacts users leveraging IPv6 due to inadequate rate limiting in Nextcloud.

Contact

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