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Not in CISA KEV

CVE-2010-1666 python-cjson

Fix: AGProjects/python-cjson@dc2b878

CVE-2010-1666 is a Buffer Overflow vulnerability in python-cjson. A fix is available for python-cjson — see the affected versions and patch details below.

Improper Restriction of Operations within the Bounds of a Memory Buffer in python-cjson

Also known asPYSEC-2010-30
Published
May 17, 2022
Updated
Oct 15, 2024
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Sep 18, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
1.7%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs76th percentile — riskier than 76% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected
🐍python-cjson

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

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 involving crafted Unicode input to the cjson.encode function.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐍PyPIpython-cjsonall versions1.0.5.1pip install --upgrade 'python-cjson==1.0.5.1'

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for python-cjson, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update python-cjson to 1.0.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2010-1666 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2010-1666 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2010-1666. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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 involving crafted Unicode input to the cjson.encode function.
O3 Security · Impact-Aware SCA

Is CVE-2010-1666 in your dependencies?

O3 Security finds CVE-2010-1666 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

CVE-2010-1666: python-cjson | O3 Security