Vulnerability in Nextcloud Server
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. This could potentially result in an attacker bypassing rate-limit controls such as the Nextcloud brute-force protection.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.017 (77.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 77th percentile — 77.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: 0.000
Affected products
- Nextcloud Server
- Fedoraproject Fedora — versions 33, 34
- Nextcloud Server — versions Fixed in 19.0.11, 20.0.10, 21.0.2
Weakness classification (CWE)
References
- hackerone.com/reports/1154003 (Permissions Required, Third Party Advisory)
- nextcloud.com/security/advisory/ (Broken Link)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2021-22915?
- CVE-2021-22915 is a critical-severity vulnerability in Nextcloud Server, classified under Improper Restriction of Excessive Authentication Attempts. CVSS score: 9.8/10. Published 2021-06-11.
- How severe is CVE-2021-22915?
- Critical severity. CVSS v3 base score is 9.8 out of 10.