CVE-2021-23438

Public Exploit
Prototype Pollution

Description

This affects the package mpath before 0.8.4. A type confusion vulnerability can lead to a bypass of CVE-2018-16490. In particular, the condition ignoreProperties.indexOf(parts[i]) !== -1 returns -1 if parts[i] is ['__proto__']. This is because the method that has been called if the input is an array is Array.prototype.indexOf() and not String.prototype.indexOf(). They behave differently depending on the type of the input.

Category

5.6
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.15%
Third-Party Advisory github.com Third-Party Advisory snyk.io Third-Party Advisory snyk.io
Affected: n/a mpath
Published at:
Updated at:

References

Link Tags
https://snyk.io/vuln/SNYK-JS-MPATH-1577289 third party advisory exploit
https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1579548 third party advisory exploit
https://github.com/aheckmann/mpath/commit/89402d2880d4ea3518480a8c9847c541f2d824fc third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-23438?
CVE-2021-23438 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23438?
To fix CVE-2021-23438, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-23438 being actively exploited in the wild?
It is possible that CVE-2021-23438 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23438?
CVE-2021-23438 affects n/a mpath.
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