#VU54557 Session Fixation in Craft CMS - CVE-2021-27903

Vulnerability identifier: #VU54557

Vulnerability risk: High

CVSSv4.0: 7.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-27903

CWE-ID: CWE-384

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Craft CMS
Web applications / CMS

Vendor: Pixel & Tonic, Inc.

Description

The vulnerability allows a remote attacker to compromise the affected application.

The vulnerability exists due to session fixation issue. A remote attacker can hijack administrator's session and gain full access to the web application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Craft CMS: 3.6.0 - 3.6.6

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External links
https://github.com/craftcms/cms/blob/develop/CHANGELOG.md#367---2021-02-23
https://github.com/craftcms/cms/blob/develop/CHANGELOG.md#security
https://github.com/craftcms/cms/commit/c17728fa0bec11d3b82c34defe0930ed409aec38

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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