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PYSEC-2020-176
Vulnerability from pysec - Published: 2020-02-19 04:15 - Updated: 2020-03-01 00:15
VLAI
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Impacted products
| Name | purl | pyyaml | pkg:pypi/pyyaml |
|---|
Aliases
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "pyyaml",
"purl": "pkg:pypi/pyyaml"
},
"ranges": [
{
"events": [
{
"introduced": "5.1"
},
{
"fixed": "5.2b1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"5.1",
"5.1.1",
"5.1.2"
]
}
],
"aliases": [
"CVE-2019-20477",
"GHSA-3pqx-4fqf-j49f"
],
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "PYSEC-2020-176",
"modified": "2020-03-01T00:15:00Z",
"published": "2020-02-19T04:15:00Z",
"references": [
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
}
]
}
BREW-VINT-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:46 – Updated: 2026-09-10 01:34 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "vint",
"purl": "pkg:brew/vint"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.3.21_2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-vint-CVE-2019-20477",
"modified": "2026-09-10T01:34:07Z",
"published": "2026-08-13T17:46:52Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-VS-PREVIEW-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:48 – Updated: 2026-09-10 21:20 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "vs-preview",
"purl": "pkg:brew/vs-preview"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.20.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-vs-preview-CVE-2019-20477",
"modified": "2026-09-10T21:20:25Z",
"published": "2026-08-13T17:48:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-VUNNEL-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:48 – Updated: 2026-09-10 01:35 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "vunnel",
"purl": "pkg:brew/vunnel"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.63.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-vunnel-CVE-2019-20477",
"modified": "2026-09-10T01:35:37Z",
"published": "2026-08-13T17:48:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-WEST-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:52 – Updated: 2026-09-10 21:24 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "west",
"purl": "pkg:brew/west"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.5.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-west-CVE-2019-20477",
"modified": "2026-09-10T21:24:20Z",
"published": "2026-08-13T17:52:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-WOOB-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:54 – Updated: 2026-09-10 01:41 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "woob",
"purl": "pkg:brew/woob"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.7_9"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-woob-CVE-2019-20477",
"modified": "2026-09-10T01:41:06Z",
"published": "2026-08-13T17:54:06Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-XML2RFC-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:54 – Updated: 2026-09-10 01:41 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "xml2rfc",
"purl": "pkg:brew/xml2rfc"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.34.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-xml2rfc-CVE-2019-20477",
"modified": "2026-09-10T01:41:12Z",
"published": "2026-08-13T17:54:12Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-XXH-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:54 – Updated: 2026-09-10 01:42 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "xxh",
"purl": "pkg:brew/xxh"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.8.14"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-xxh-CVE-2019-20477",
"modified": "2026-09-10T01:42:04Z",
"published": "2026-08-13T17:54:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-YAMALE-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:54 – Updated: 2026-09-10 01:42 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "yamale",
"purl": "pkg:brew/yamale"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "6.1.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-yamale-CVE-2019-20477",
"modified": "2026-09-10T01:42:04Z",
"published": "2026-08-13T17:54:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
BREW-YAMLLINT-CVE-2019-20477 (GHSA-3PQX-4FQF-J49F)
Vulnerability from osv_homebrew – Published: 2026-08-13 17:54 – Updated: 2026-09-17 18:37 – Source website
VLAI
Summary
Deserialization of Untrusted Data in PyYAML
Details
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
9.8 (Critical)
References
| URL | Type | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||||||||||||||||
{
"affected": [
{
"ecosystem_specific": {
"fix": "bump",
"range_state": "fixed",
"resource": "pyyaml",
"resource_purl": "pkg:pypi/pyyaml@6.0.3",
"upstream_fixed_in": "5.2"
},
"package": {
"ecosystem": "Homebrew",
"name": "yamllint",
"purl": "pkg:brew/yamllint"
},
"ranges": [
{
"events": [
{
"introduced": "1.16.0"
},
{
"fixed": "1.19.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"confidence": "high",
"source": "matched",
"strategy": "registry",
"upstream_evidence": [
{
"ecosystem": "PyPI",
"key": "pkg:pypi/pyyaml@6.0.3",
"name": "pyyaml",
"resource": "pyyaml",
"strategy": "registry",
"subject_version": "6.0.3"
}
]
},
"details": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.",
"id": "BREW-yamllint-CVE-2019-20477",
"modified": "2026-09-17T18:37:10Z",
"published": "2026-08-13T17:54:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-20477"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-3pqx-4fqf-j49f"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/pyyaml/PYSEC-2020-176.yaml"
},
{
"type": "PACKAGE",
"url": "https://github.com/yaml/pyyaml"
},
{
"type": "WEB",
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/download/47655"
}
],
"schema_version": "1.7.3",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Deserialization of Untrusted Data in PyYAML",
"upstream": [
"GHSA-3pqx-4fqf-j49f",
"CVE-2019-20477",
"PYSEC-2020-176"
]
}
CVE-2019-20477 (GCVE-0-2019-20477)
Vulnerability from cvelistv5 – Published: 2020-02-19 03:09 – Updated: 2024-08-05 02:39
VLAI
EPSS
VEX
Summary
PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342.
Severity
No CVSS data available.
CWE
- n/a
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/yaml/pyyaml/blob/master/CHANGES | x_refsource_MISC |
| https://www.exploit-db.com/download/47655 | x_refsource_MISC |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisoryx_refsource_FEDORA |
| https://lists.fedoraproject.org/archives/list/pac… | vendor-advisoryx_refsource_FEDORA |
{
"containers": {
"adp": [
{
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"dateUpdated": "2024-08-05T02:39:10.138Z",
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},
"references": [
{
"tags": [
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"x_transferred"
],
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
"tags": [
"x_refsource_MISC",
"x_transferred"
],
"url": "https://www.exploit-db.com/download/47655"
},
{
"name": "FEDORA-2020-3162499159",
"tags": [
"vendor-advisory",
"x_refsource_FEDORA",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/"
},
{
"name": "FEDORA-2020-e84e90dc4a",
"tags": [
"vendor-advisory",
"x_refsource_FEDORA",
"x_transferred"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/"
}
],
"title": "CVE Program Container"
}
],
"cna": {
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"vendor": "n/a",
"versions": [
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"value": "PyYAML 5.1 through 5.1.2 has insufficient restrictions on the load and load_all functions because of a class deserialization issue, e.g., Popen is a class in the subprocess module. NOTE: this issue exists because of an incomplete fix for CVE-2017-18342."
}
],
"problemTypes": [
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"type": "text"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2020-03-01T00:06:04.000Z",
"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"shortName": "mitre"
},
"references": [
{
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],
"url": "https://github.com/yaml/pyyaml/blob/master/CHANGES"
},
{
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],
"url": "https://www.exploit-db.com/download/47655"
},
{
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"tags": [
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],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52N5XS73Z5S4ZN7I7R56ICCPCTKCUV4H/"
},
{
"name": "FEDORA-2020-e84e90dc4a",
"tags": [
"vendor-advisory",
"x_refsource_FEDORA"
],
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/33VBUY73AA6CTTYL3LRWHNFDULV7PFPN/"
}
],
"x_legacyV4Record": {
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"ID": "CVE-2019-20477",
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},
"affects": {
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}
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Trend slope:
-
(linear fit over daily sighting counts)
Show additional events:
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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