Description
This affects all versions of package mout. The deepFillIn function can be used to 'fill missing properties recursively', while the deepMixIn 'mixes objects into the target object, recursively mixing existing child objects as well'. In both cases, the key used to access the target object recursively is not checked, leading to a Prototype Pollution.
Remediation
References
https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1050373
https://snyk.io/vuln/SNYK-JS-MOUT-1014544
https://github.com/mout/mout/blob/master/src/object/deepMixIn.js
https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARS-1050374
https://github.com/mout/mout/blob/master/src/object/deepFillIn.js