CVE-2010-1666: Buffer Overflow in python-cjson

python-cjson Updated 02 Oct 2025

Summary

02/07/2010
Yes i
Moderate
6.9

CVE-2010-1666: Buffer overflow in Dan Pascu python-cjson 1.0.5, when UCS-4 encoding is enabled, allows context-dependent attackers to cause a denial of service (application crash) or possibly have unspecified other impact via vectors i... Affects python-cjson versions < 1.1.0. Fixed in 1.1.0. How to fix ↓

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Background

python-cjson is a Python extension module that provides a fast JSON encoder/decoder for Python. It is commonly used to serialize and deserialize JSON data. The vulnerability affects version 1.0.5 of python-cjson when UCS-4 encoding is enabled.

Vulnerability Detail

The vulnerability is a buffer overflow that can be triggered by passing crafted Unicode input to the cjson.encode function. This can lead to a denial of service (application crash) or potentially have other unspecified impacts. The issue arises due to a lack of proper input validation and handling of Unicode input.

How To Fix

Minimum fixed version

1.1.0

This is the first release that contains the fix.

pip install --upgrade "python-cjson==1.1.0"

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Workaround

There is no specific workaround mentioned for this vulnerability.

Conclusion

The buffer overflow vulnerability in python-cjson can lead to a denial of service or other potential impacts. It is recommended to upgrade to version 1.1.0 or later to mitigate the issue. For further support on vulnerability remediation, please contact DevNack.com.

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FAQ

python-cjson is a Python extension module for fast JSON encoding/decoding.

Version 1.0.5 of python-cjson is affected.

The vulnerability can cause a denial of service (application crash) or have other unspecified impacts.

Upgrade to version 1.1.0 or later of python-cjson.

No specific workaround has been mentioned for this vulnerability.

Related vulnerabilities

Recent vulnerabilities recorded for python-cjson.

How To Fix

Minimum fixed version

1.1.0

This is the first release that contains the fix.

pip install --upgrade "python-cjson==1.1.0"

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