CVE-2020-1747
highpriority · track · 41EPSS 0.054 · 93 %ileEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9.3–10
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (19)
Products and version ranges known to be affected.
- oracle communications cloud native core network function cloud native environment= 22.1.0nvdUScpe:2.3:a:oracle:communications_cloud_native_core_network_function_cloud_native_environment:*:*:*:*:*:*:*:*
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-6757-jp84-gxfxImproper Input Validation in PyYAML2021-04-20ghsa · osvUS
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.
- PYSEC-2020-962020-03-24vendor · osvUS
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.
also known as (7)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (44)
External citations — patches, advisories, analysis.
- http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00017.htmlcnnvd
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00017.htmlcnnvd
- https://access.redhat.com/security/cve/cve-2020-1747cnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1747cnnvd
- https://github.com/yaml/pyyaml/pull/386cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7PPAS6C4SZRDQLR7C22A5U3QOLXY33JX/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/K5HEPD7LEVDPCITY5IMDYWXUMX37VFMY/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MMQXSZXNJT6ERABJZAAICI3DQSQLCP3D/cnnvd
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