#VU35581 Cross-site scripting in TeamCity - CVE-2019-15848

Vulnerability identifier: #VU35581

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-2019-15848

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
TeamCity
Web applications / CRM systems

Vendor: JetBrains s.r.o.

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. The vulnerability allows cross-site scripting (XSS), potentially making it possible to send an arbitrary HTTP request to a TeamCity server under the name of the currently logged-in 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 update from vendor's website.

Vulnerable software versions

TeamCity: 2019.1 - 2019.1.1

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External links
https://blog.jetbrains.com/teamcity/2019/09/important-security-notice-xss-vulnerability-allowing-rce/
https://gist.github.com/JLLeitschuh/fe6784391254b58de680bbda78a04a70
https://twitter.com/JLLeitschuh/status/1169332316612644864?s=20
https://www.softwaresecured.com/jetbrains-teamcity-reflected-xss/

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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.