CVE-2014-4616: Array index error in the scanstring function in the _json module in Python 2.7 through 3.5 and simplejson befo

This week

MEDIUM 5.9REMOTEUPGRADEUPGRADEMITIGATE

CVE-2014-4616 is a medium-severity flaw (CVSS 5.9) affecting python, simplejson, opensuse. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

EPSS top 5%: very likely to be exploited
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	5.9 (Medium)
Attack vector	Network (remote)
Attack complexity	High
Privileges needed	None
User interaction	None
EPSS exploit chance	7.8% (top 5%)
CISA exploited list	No
Weakness	CWE-129
Published	2017-08-24
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: opensuse · opensuse project · python · simplejson project

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2017-08-24 20:29 UTCPublished CVE record published
2026-06-17 00:10 UTCUpdated Record last modified

python python UPGRADE

Affected: >= 2.7.0 and < 2.7.7 · >= 3.0.0 and < 3.2.6 · >= 3.3.0 and < 3.3.6 · >= 3.4.0 and < 3.4.1

Fixed in: 2.7.7, 3.2.6, 3.3.6, 3.4.1

Safe to downgrade to: a release before 2.7.0

1. Check installed version

apt-cache policy python || rpm -q python || python --version

2. UPGRADE to 2.7.7 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade python

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade python

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 2.7.0 (Debian / Ubuntu)

apt-cache madison python sudo apt install python=<VERSION_BEFORE_2.7.0> sudo apt-mark hold python

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list python sudo dnf downgrade python-<VERSION_BEFORE_2.7.0> sudo dnf versionlock add python

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

simplejson project simplejson UPGRADE

Affected: < 2.6.1

Fixed in: 2.6.1

Safe to downgrade to: no unaffected older release

1. Check installed version

pip show simplejson

2. UPGRADE to 2.6.1

pip install --upgrade "simplejson>=2.6.1"

opensuse opensuse MITIGATE

Affected: 13.1

Fixed in: no fixed release known

Safe to downgrade to: a release before 13.1

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

opensuse project opensuse MITIGATE

Affected: 12.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 12.3

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2014-4616?

python: upgrade to 2.7.7, 3.2.6, 3.3.6, 3.4.1; simplejson: upgrade to 2.6.1; opensuse: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2014-4616 being exploited?

CVE-2014-4616 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2014-4616 affect?

CVE-2014-4616 affects python, simplejson, opensuse. Severity is medium (CVSS 5.9). 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

How urgent is CVE-2014-4616?

Priority 54/100. EPSS top 5%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

Python vulnerabilities

Related CVEs

CVE-2024-9287 HIGH 7.8 UPGRADE A vulnerability has been found in the CPython `venv` module and CLI where path names provided when creating a
CVE-2026-3087 HIGH 7.5 UPGRADE If `shutil.unpack_archive()` is given a ZIP archive with an absolute Windows path containing a drive (`C:\\...
CVE-2026-6019 MEDIUM 6.1 UPGRADE http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string co
CVE-2026-7210 HIGH 7.5 UPGRADE `xml.parsers.expat` and `xml.etree.ElementTree` use insufficient entropy for Expat hash-flooding protection, w
CVE-2026-0864 MEDIUM 5.5 UPGRADE When using the "configparser" module to write configuration files containing multi-line text values with carri

References

← Back to latest CVEs