CVE-2014-4616: simplejson before 2.6.1 vulnerable to array index error

simplejson Updated 02 Oct 2025

Summary

14/05/2022
Yes i
Moderate
5.9

CVE-2014-4616: simplejson before 2.6.1 vulnerable to array index error. Affects simplejson versions < 2.6.1. Fixed in 2.6.1. How to fix ↓

Also tracked for

The same CVE-2014-4616 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.

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Background

simplejson is a Python library that provides a fast and efficient way to encode and decode JSON data. It is widely used in various Python applications and frameworks. However, versions of simplejson before 2.6.1 are susceptible to an array index error vulnerability.

Vulnerability Detail

The vulnerability exists in the scanstring function of the _json module in Python 2.7 through 3.5 and simplejson before 2.6.1. It allows context-dependent attackers to read arbitrary process memory by exploiting a negative index value in the idx argument of the raw_decode function. This vulnerability can potentially lead to unauthorized access to sensitive information stored in the process memory.

How To Fix

Minimum fixed version

2.6.1

This is the first release that contains the fix.

pip install --upgrade "simplejson==2.6.1"

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Workaround

There is no known workaround for this vulnerability. It is essential to apply the fix by upgrading to the patched version of simplejson.

Conclusion

In conclusion, the simplejson package before version 2.6.1 is vulnerable to an array index error. This vulnerability can be mitigated by upgrading to the latest version of the package. For further assistance with vulnerability remediation, please contact DevNack.com.

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FAQ

simplejson is a Python library used for encoding and decoding JSON data.

Versions of simplejson before 2.6.1 are vulnerable to this array index error.

This vulnerability allows attackers to read arbitrary process memory, potentially leading to unauthorized access to sensitive information.

To fix this vulnerability, upgrade the simplejson package to version 2.6.1 or later.

No, there is no known workaround for this vulnerability. It is crucial to apply the fix by upgrading the package.

How To Fix

Minimum fixed version

2.6.1

This is the first release that contains the fix.

pip install --upgrade "simplejson==2.6.1"

Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →

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