#VU53056 Cross-site scripting in Joplin - CVE-2020-28249

Vulnerability identifier: #VU53056

Vulnerability risk: Low

CVSSv4.0: 0.3 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:P/U:Clear]

CVE-ID: CVE-2020-28249

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Joplin
Client/Desktop applications / Software for archiving

Vendor: Joplinapp

Description

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks via a LINK element in a note.

The vulnerability exists due to insufficient sanitization of user-supplied data passed via a LINK element in a note. A remote user can inject 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
Install update from vendor's website.

Vulnerable software versions

Joplin: 1.0.62 - 1.2.5

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External links
https://github.com/fhlip0/JopinXSS

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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. However, proof of concept for this vulnerability is available.