CVE-2021-22915

Description

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.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.49%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org
Affected: n/a Nextcloud Server
Published at:
Updated at:

References

Link Tags
https://hackerone.com/reports/1154003 third party advisory permissions required
https://nextcloud.com/security/advisory/?id=NC-SA-2021-009 broken link
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L6BO6P6MP2MOWA6PZRXX32PLWPXN5O4S/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AGXGR6HYGQ6MZXISMJEHCOXRGRFRUFMA/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-22915?
CVE-2021-22915 has been scored as a critical severity vulnerability.
How to fix CVE-2021-22915?
To fix CVE-2021-22915, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-22915 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-22915 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-22915?
CVE-2021-22915 affects n/a Nextcloud Server.
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