Brute Force Attack Vulnerability in Nextcloud Server
CVE-2021-22915

9.8CRITICAL

Key Information:

Vendor

Nextcloud
Status
Nextcloud Server
Vendor
CVE Published:
11 June 2021

What is CVE-2021-22915?

Nextcloud Server versions prior to 19.0.11, 20.0.10, and 21.0.2 exhibit a vulnerability that makes them susceptible to brute force attacks. This issue arises from the failure to incorporate IPv6 subnets into the existing rate-limiting mechanisms, effectively allowing attackers to bypass protective measures designed to thwart repeated login attempts. Consequently, this oversight endangers the security of user accounts and sensitive data managed by Nextcloud servers.

Affected Version(s)

Nextcloud Server Fixed in 19.0.11, 20.0.10, 21.0.2

References

https://hackerone.com/reports/1154003
x_refsource_MISC
https://nextcloud.com/security/advisory/?id=NC-SA-2021-009
x_refsource_MISC
https://lists.fedoraproject.org/archives/list/package-ann...
vendor-advisoryx_refsource_FEDORA

CVSS V3.1

Score:
9.8
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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CVE-2021-22915 : Brute Force Attack Vulnerability in Nextcloud Server