CVE-2017-18342: Input Validation

Published Jun 27, 2018
·
Updated

In PyYAML before 4.1, the yaml.load() API could execute arbitrary code. In other words, yaml.safeload is not used.

Other sources

In PyYAML before 5.1, the yaml.load() API could execute arbitrary code if used with untrusted data. The load() function has been deprecated in version 5.1 and the 'UnsafeLoader' has been introduced for backward compatibility with the function.

It was found that using yaml.load() API on untrusted input could lead to arbitrary code execution.

References:

http://seclists.org/oss-sec/2018/q2/240

Affected Software

11 affected componentsFixes available
redhat/PyYAML<5.1
5.1
pip/pyyaml<4.1
4.1
PyYAML PyYAML<5.1
Fedoraproject Fedora=28
Fedoraproject Fedora=29
Fedoraproject Fedora=30
F5 BIG-IP>=17.1.0<=17.5.0
F5 BIG-IP>=16.1.0<=16.1.5
F5 BIG-IP>=15.1.0<=15.1.10
F5 BIG-IQ Centralized Management>=8.1.0<=8.4.0
IBM Edge Application Manager<=4.5

Remediation

Event History

Jun 27, 2018
CVE Published
12:00 AM
Data Sourced
12:00 AM
RemedyDescriptionSeverityWeakness
CVE Published
via MITRE·12:00 PM
Data Sourced
via MITRE·12:00 PM
Description
Jan 4, 2019
Advisory Published
via GitHub·05:45 PM
Aug 20, 2025
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2017-18342?

CVE-2017-18342 is a vulnerability in PyYAML that allows arbitrary code execution.

2

How severe is CVE-2017-18342?

CVE-2017-18342 has a severity rating of 9.8, which is considered critical.

3

Which versions of PyYAML are affected by CVE-2017-18342?

Versions up to and including 4.1 of PyYAML are affected by CVE-2017-18342.

4

How can I fix CVE-2017-18342?

To fix CVE-2017-18342, you should upgrade to version 5.1 or newer of PyYAML.

5

Where can I find more information about CVE-2017-18342?

You can find more information about CVE-2017-18342 at the following references: [link1], [link2], [link3].

Contact

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