SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-22915

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.

CRITICAL 9.8EPSS 1.74%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.74%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.74% probability · 76th percentile
CISA KEV
Not listed
Weakness
CWE-307
Affected
nextcloud/nextcloud server · fedoraproject/fedora
Source
support@hackerone.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.