#VU179 Cross-site scripting in TYPO3 backend in TYPO3

Vulnerability identifier: #VU179

Vulnerability risk: High

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

CVE-ID: N/A

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
TYPO3
Web applications / CMS

Vendor: TYPO3

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

The vulnerability exists due to improper filtering HTML code from user-supplied input before displaying the input. A remote user can cause arbitrary scripting code to be executed by the target user's browser. The code will originate from the site running the TYPO3 software. As a result, the code will be able to access the target user's cookies, associated with the site, access data recently submitted by the target user via web form to the site, or take actions on the site acting as the target user.

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
Install the latest versions (6.2.26, 7.6.10, 8.2.1).

Vulnerable software versions

TYPO3: 6.2.0 rc1 - 6.2.25, 7.6.0 - 7.6.9, 8.0.0 - 8.2.0

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External links
https://typo3.org/teams/security/security-bulletins/typo3-core/typo3-core-sa-2016-014/

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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.