#VU57216 Prototype pollution in immer - CVE-2021-23436

Vulnerability identifier: #VU57216

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-2021-23436

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
immer
Web applications / JS libraries

Vendor: immer

Description

The vulnerability allows a remote attacker to execute arbitrary JavaScript code.

The vulnerability exists due to improper input validation. A remote attacker can send a specially crafted request to the application and perform prototype pollution.

Note, the vulnerability exists due to incomplete fix for #VU57215.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

immer: 8.0.1 - 9.0.5

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External links
https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1579266
https://snyk.io/vuln/SNYK-JS-IMMER-1540542
https://github.com/immerjs/immer/commit/fa671e55ee9bd42ae08cc239102b665a23958237

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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.