CVE-2021-41177

mediumpriority · track · 33EPSS 0.015 · 75 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.55% (75th) EPSS

CVSS 5.5 · medium

Is it mine?

6 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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`.

cvss

Technical severity, 0–10. One row per scoring source.

8.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.5–8.1

v2.05.5mediumAV:N/AC:L/Au:S/C:P/I:N/A:Pprimary · NVD / NIST USexploitability 8 · impact 4.9

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.2

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · ENISA EU

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · security-advisories@github.comexploitability 2.8 · impact 5.2

v3.17.4highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-799US

affected products (6)

Products and version ranges known to be affected.

nextcloud security-advisories≤ < 20.0.13enisa_euvdEU
nextcloud security-advisories≤ < 22.2.0enisa_euvdEU
nextcloud security-advisories21.0.0, → 21.0.5enisa_euvdEU
nextcloud nextcloud server< 20.0.13nvdUScpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*
nextcloud nextcloud server21.0.0 → 21.0.5nvdUScpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*
nextcloud nextcloud server22.0.0 → 22.2.0nvdUScpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:*

also known as (2)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-10-25modified 2026-06-17

references (15)

External citations — patches, advisories, analysis.

scry

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