CVE-2020-1747

CRITICAL
9.8
CVSS Score
Published: March 24, 2020 at 01:56 PM UTC
Updated: June 17, 2026 at 03:02 AM UTC
4 products affected across 4 vendorsFedoraLeapCommunications Cloud Native Core Network Function Cloud Native Environment

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Severity
CRITICAL9.8
Exploit prediction
EPSS 5%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

5.1 ≤ v < 5.3.15.3.1
Affected range stops below 5.3.1, so it looks safe — our inference, not a vendor statement

CVSS

9.8CRITICALredhat
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-20

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