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CVE-2021-32728

End-to-end encryption device setup did not verify public key

Published: Aug 18, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-295
6.5MEDIUM
NVD MITRE
EPSS Score
0.9%
Top 45.2%
CISA KEV
Not in KEV
Exploits
2 Known
Remediation
Patch Available
Self-Check
OpenVAS

Description

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with a computer. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.3.0, the Nextcloud Desktop client fails to check if a private key belongs to previously downloaded public certificate. If the Nextcloud instance serves a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. This issue is fixed in Nextcloud Desktop Client version 3.3.0. There are no known workarounds aside from upgrading.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-295

Affected Products

nextcloud
oss-project·DEaka nextcloud server
desktopOn-premDesktop App
Cloud & SaaS / saas-application
security-advisoriesSaaSSaaS Service
Cloud & SaaS / saas-application
debian
oss-project·GBaka debian gnu/linux
debian linuxOn-premOS
Operating Systems / linux-distro
Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
Nextcloud GmbH
commercial·DEaka nextcloud enterprise server, nextcloud server, nextcloud calendar
NextcloudSaaSSaaS Service
Cloud & SaaS / saas-application

Exploitability

2 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://github.com/nextcloud/desktop/pull/3338
github.com
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-f5fr-5gcv-6cc5
github.com
https://hackerone.com/reports/1189162
hackerone.com
and 6 more references View all →

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