How severe is CVE-2014-4616?

CVE-2014-4616 has a CVSS score of 5.9/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2014-4616?

CVE-2014-4616 affects the following packages: simplejson (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2014-4616?

Update simplejson to 2.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2014-4616 is resolved across your whole dependency graph.

How do I detect CVE-2014-4616 in my PyPI dependencies?

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

How do I mitigate CVE-2014-4616 if there is no patch (or I can't update yet)?

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.

Is CVE-2014-4616 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2014-4616, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2014-4616?

CVE-2014-4616 has an EPSS (Exploit Prediction Scoring System) score of 7.8%, placing it in the 95th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2014-4616?

CVE-2014-4616 is classified as CWE-129 (CWE-129). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2014-4616 published, and has it been updated?

CVE-2014-4616 was published on August 24, 2017 and was last updated on July 7, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍

🐍 PyPI

Not in CISA KEV

MEDIUM severity

CVE-2014-4616 — simplejson

MEDIUM

CVE-2014-4616 is a medium-severity (CVSS 5.9) CWE-129 vulnerability in simplejson. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for simplejson — see the affected versions and patch details below.

simplejson before 2.6.1 vulnerable to array index error

Also known asGHSA-9772-cwx9-r4cjPSF-2017-1PYSEC-2026-921

Published

Aug 24, 2017

Updated

Jul 7, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

1 known

Exploitation data as of Nov 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

7.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs95th percentile — riskier than 95% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

🐍simplejson

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

Array index error in the scanstring function in the _json module in Python 2.7 through 3.5 and simplejson before 2.6.1 allows context-dependent attackers to read arbitrary process memory via a negative index value in the idx argument to the raw_decode function.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`simplejson`	all versions	2.6.1`pip install --upgrade 'simplejson==2.6.1'`

Affected Products

4 products · 7 configurations

opensuseopensuse

1 version

13.1

opensuseopensuse_project

1 version

12.3

Application

pythonpython

≥ 3.4.0 && < 3.4.1

range

Application

simplejsonsimplejson_project

< 2.6.1

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Array index error in the scanstring function in the _json module in Pyth…

hackerone.comNVDOct 2018

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simplejson, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update simplejson to 2.6.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2014-4616 is resolved across your whole dependency graph.
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.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

This issue affects the versions of python as shipped with Red Hat Enterprise Linux 7, the versions of python-simplejson as shipped with Red Hat Enterprise Linux 5 and 6, and the versions of python33-python and python33-python-simplejson as shipped with Red Hat Software Collections. Red Hat Product Security has rated…

Product	Fixed in	Advisory
Red Hat Enterprise Linux 7	`python-0:2.7.5-34.el7`	RHSA-2015:2101
Red Hat Satellite 6.0	`python-anyjson-0:0.3.3-4.el6sat`	RHEA-2014:1175
Red Hat Software Collections for Red Hat Enterprise Linux 6	`python27-0:1.1-17.el6`	RHSA-2015:1064

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2014-4616 in your dependencies?

Find it across PyPI, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

5.9/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Raw vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

CWE Classification

CWE-129CWE-129

Weaponization

No Nuclei template or Metasploit module yet. 1 public proof-of-concept reference is listed on this page.

OpenSSF Scorecard

Package health score

simplejson

5.6/10

Code-Review5/10

Maintained10/10

Branch-Protection3/10

Assessed Oct 19, 2026

Timeline

Disclosed

Aug 24, 2017

First exploit

Oct 30, 2018

Last updated

Jul 7, 2026

Identifiers

CVE-2014-4616

GHSA-9772-cwx9-r4cj

PSF-2017-1

PYSEC-2026-921

References

Advisorybugs.python.org · issue21529 Advisorylists.opensuse.org · msg00015 Advisoryopenwall.com Advisoryrhn.redhat.com · RHSA 2015 1064 Advisorysecurityfocus.com Advisorybugs.debian.org · bugreport.cgi Advisorybugzilla.redhat.com · show bug.cgi Advisoryhackerone.com Advisorysecurity.gentoo.org · 201503 10 Advisorynvd.nist.gov · CVE 2014 4616 Packagegithub.com · simplejson

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs with CWE-129 are rated as high or higher (top: high).

CVE-2026-116585CVE-2026-115916CVE-2026-116590CVE-2026-77375CVE-2026-107211CVE-2026-107225CVE-2026-107218CVE-2026-107217Browse all CWE-129

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedJul 7, 2026

CVE-2014-4616 — simplejson

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2014-4616 in your dependencies?