Vulnerability identifier: #VU56824

Vulnerability risk: Low

CVSSv3.1: 5.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:U/RC:C]

CVE-ID: CVE-2021-38320

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
simpleSAMLphp Authentication
Web applications / Modules and components for CMS

Vendor: David O'Callaghan

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data within the $_SERVER["PHP_SELF"] value in the ~/simplesamlphp-authentication.php file. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

simpleSAMLphp Authentication: 0.1 - 0.7.0

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External links
http://www.wordfence.com/vulnerability-advisories/#CVE-2021-38320
http://plugins.trac.wordpress.org/browser/simplesamlphp-authentication/tags/0.7.0/simplesamlphp-authentication.php#L307

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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.