Medium severity · published Jun 11, 2021
CVE-2021-22895
Nextcloud Desktop Client before 3.3.1 is vulnerable to improper certificate validation due to lack of SSL certificate verification when using the "Register with a Provider" flow
5.9
CVSS
1%
EPSS
No
On KEV
Description
Nextcloud Desktop Client before 3.3.1 is vulnerable to improper certificate validation due to lack of SSL certificate verification when using the "Register with a Provider" flow.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 64% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
10.0; 11.0 · source: NVD
DE
Desktop · Nextcloud
before 3.1.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22895
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22895
Patch
https://github.com/nextcloud/desktop/pull/2926
Release Notes
https://github.com/nextcloud/desktop/releases/tag/v3.1.3
Third Party Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-qpgp-vf4p-wcw5
Exploit
https://hackerone.com/reports/903424
Third Party Advisory
https://www.debian.org/security/2021/dsa-4974
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