#VU41989 Prototype polution in Lodash - CVE-2020-8203

Vulnerability identifier: #VU41989

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-8203

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Lodash
Web applications / JS libraries

Vendor: Lodash

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 when using _.zipObjectDeep in lodash. A remote attacker can inject and execute arbitrary script code.

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

Lodash: 4.17.0 - 4.17.15

---

External links
https://github.com/lodash/lodash/issues/4874
https://hackerone.com/reports/712065
https://security.netapp.com/advisory/ntap-20200724-0006/
https://www.npmjs.com/advisories/1523

---

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.