#VU57648 Authorization bypass through user-controlled key in Deck - CVE-2021-39225

Vulnerability identifier: #VU57648

Vulnerability risk: Medium

CVSSv4.0: 6.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-39225

CWE-ID: CWE-639

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Deck
Mobile applications / Apps for mobile phones

Vendor: Nextcloud

Description

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to a missing permission check. A remote authenticated attacker can access Deck cards of another user.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Deck: 1.2.0 - 1.5.2

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External links
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-2x96-38qg-3m72
https://github.com/nextcloud/deck/pull/3316
https://hackerone.com/reports/1331728

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.