#VU7653 Cross-site scripting in PHPMailer - CVE-2017-11503

Vulnerability identifier: #VU7653

Vulnerability risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-11503

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
PHPMailer
Web applications / Other software

Vendor: phpmailer.sourceforge.net

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

The vulnerability exists due to insufficient validation of user-supplied data passed via specially crafted parameter to 'code_generator.phps' example script. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in victim’s browser in security 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
Update to version 5.2.24.

Vulnerable software versions

PHPMailer: 5.2 - 5.2.23

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External links
https://packetstormsecurity.com/files/143138/phpmailer-xss.txt

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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.