Improper Input Validation Affecting py3-yaml package, versions <5.3.1-r0


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
5.44% (93rd percentile)

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  • Snyk IDSNYK-ALPINE324-PY3YAML-17298033
  • published11 Jun 2026
  • disclosed24 Mar 2020

Introduced: 24 Mar 2020

CVE-2020-1747  (opens in a new tab)
CWE-20  (opens in a new tab)

How to fix?

Upgrade Alpine:3.24 py3-yaml to version 5.3.1-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream py3-yaml package and not the py3-yaml package as distributed by Alpine. See How to fix? for Alpine:3.24 relevant fixed versions and status.

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.

References

CVSS Base Scores

version 3.1