Nextcloud is an open-source, self-hosted productivity platform. Prior to versions 20.0.13, 21.0.5, and 22.2.0, Nextcloud Server did not implement a database backend for rate-limiting purposes. Any component of Nextcloud using rate-limits (as as AnonRateThrottle or UserRateThrottle) was thus not rate limited on instances not having a memory cache backend configured. In the case of a default installation, this would notably include the rate-limits on the two factor codes. It is recommended that the Nextcloud Server be upgraded to 20.0.13, 21.0.5, or 22.2.0. As a workaround, enable a memory cache backend in config.php.
CVE-2021-41177
HIGHNVD 8.18.1—
EchelonGraph scoreMEDIUM confidence
This high-severity CVE scores 8.1 under NVD CVSS v3. EPSS exploit probability: 0.6%, top 30% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, nvd
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 2%CVSS: 8.1Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.1
- EG Score
- 8.1(medium)
- EPSS
- 71.3%
- KEV
- Not listed
Published
October 25, 2021
Last Modified
November 21, 2024
References (8)
- security-advisories@githubhttps://github.com/nextcloud/security-advisories/security/advisories/GHSA-fj39-4qx4-m3f2
- security-advisories@githubhttps://github.com/nextcloud/server/pull/28728
- security-advisories@githubhttps://hackerone.com/reports/1265709
- security-advisories@githubhttps://security.gentoo.org/glsa/202208-17
- af854a3a-2127-422b-91ae-364da2661108https://github.com/nextcloud/security-advisories/security/advisories/GHSA-fj39-4qx4-m3f2
- af854a3a-2127-422b-91ae-364da2661108https://github.com/nextcloud/server/pull/28728
- af854a3a-2127-422b-91ae-364da2661108https://hackerone.com/reports/1265709
- af854a3a-2127-422b-91ae-364da2661108https://security.gentoo.org/glsa/202208-17
Frequently asked(5)
What is CVE-2021-41177?
CVE-2021-41177 is a high vulnerability published on October 25, 2021. Nextcloud is an open-source, self-hosted productivity platform. Prior to versions 20.0.13, 21.0.5, and 22.2.0, Nextcloud Server did not implement a database backend for rate-limiting purposes. Any component of Nextcloud using rate-limits (as as AnonRateThrottle or UserRateThrottle) was thus not…
When was CVE-2021-41177 disclosed?
CVE-2021-41177 was first published in the National Vulnerability Database on October 25, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-41177 actively exploited?
CVE-2021-41177 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 71.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-41177?
CVE-2021-41177 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2021-41177?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-41177, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2021-41177
Is Your Infrastructure Affected by CVE-2021-41177?
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