Cross-site scripting in Werkzeug

1) Cross-site scripting

EUVDB-ID: #VU31406

Risk: Low

CVSSv3.1: 5.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2016-10516

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

Vulnerability allows a remote attacker to perform Cross-site scripting attacks.

An input validation error exists in the render_full function in debug/tbtools.py in the debugger in Pallets Werkzeug before 0.11.11 (as used in Pallets Flask and other products). A remote authenticated 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 0.11.11.

Vulnerable software versions

Werkzeug: 0.11.1 - 0.11.10

External links

http://blog.neargle.com/2016/09/21/flask-src-review-get-a-xss-from-debuger/
http://github.com/pallets/werkzeug/pull/1001
http://lists.debian.org/debian-lts-announce/2017/11/msg00037.html

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.