CVE-2020-7742: Prototype Pollution in simpl-schema
Summary
CVE-2020-7742: Prototype Pollution in simpl-schema. Affects simpl-schema versions < 1.10.2. Fixed in 1.10.2. How to fix ↓
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Background
simpl-schema is an npm package that provides a simple and intuitive way to define and validate JavaScript object schemas. It is commonly used in web applications to ensure data consistency and integrity. However, versions of simpl-schema prior to 1.10.2 are vulnerable to a prototype pollution attack. This means that an attacker can manipulate the schema input, potentially leading to remote code execution within the application.
Vulnerability Detail
The vulnerability in simpl-schema arises from insufficient input validation. By injecting malicious data into the schema, an attacker can modify the prototype of objects used within the application. This can result in various security issues, including remote code execution. The impact of this vulnerability depends on the context in which simpl-schema is used, but it has the potential to compromise the confidentiality, integrity, and availability of the affected application.
How To Fix
Latest published version: 3.4.8 as of 23 Oct 2026
npm install simpl-schema@3.4.8Upgrading to it may include breaking changes; the version below is the minimum fixed release for this vulnerability.
If you need the minimum change
1.10.2
This is the first release that contains the fix.
npm install simpl-schema@1.10.2Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
There is no known workaround for this vulnerability. It is crucial to update to the fixed version of simpl-schema to mitigate the risk of exploitation.
Conclusion
The simpl-schema package prior to version 1.10.2 is vulnerable to prototype pollution, which can result in remote code execution. It is crucial to update to version 1.10.2 or later to mitigate this risk. For further support on vulnerability remediation, please contact DevNack.com.
See every vulnerability recorded for simpl-schema →
FAQ
simpl-schema is an npm package used for defining and validating JavaScript object schemas.
Prototype pollution is a vulnerability that allows an attacker to modify the prototype of objects, leading to unexpected behavior and potential security issues.
The impact of this vulnerability depends on the context in which simpl-schema is used. It has the potential to result in remote code execution and compromise the confidentiality, integrity, and availability of the affected application.
To fix this vulnerability, update simpl-schema to version 1.10.2 or later by running 'npm install simpl-schema@1.10.2'.
There is no known workaround for this vulnerability. It is essential to update to the fixed version of simpl-schema.
