CVE-2020-1747

Description

A vulnerability was discovered in the PyYAML library in versions before 5.3.1, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. An attacker could use this flaw to execute arbitrary code on the system by abusing the python/object/new constructor.

How to fix CVE-2020-1747

To remediate CVE-2020-1747, upgrade the affected package to a fixed version below.

• —upgrade to 5.3.1-r0 or later
• —upgrade to 5.3-2 or later
• —upgrade to 5.3.1 or later
• —upgrade to 5.3.1 or later

Is CVE-2020-1747 being exploited?

Low — EPSS is 1.8%, meaning exploitation activity has not been observed at scale.

Affected packages (4)

• from 0, < 5.3.1-r0
• from 0, < 5.3-2
• >= 5.1b7, < 5.3.1
• >= 5.1, < 5.3.1

CVSS scores

References (24)

• ADVISORYgithub.com/advisories/GHSA-6757-jp84-gxfx
• ADVISORYnvd.nist.gov/vuln/detail/CVE-2020-1747
• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2020-1747
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2020-1747
• PATCH