PyYAML up to 4.0 API yaml.load input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in PyYAML up to 4.0. The affected element is the function yaml.load of the component API. Executing a manipulation can lead to input validation. This vulnerability is handled as CVE-2017-18342. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in PyYAML up to 4.0. This vulnerability affects the function yaml.load of the component API. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In PyYAML before 4.1, the yaml.load() API could execute arbitrary code. In other words, yaml.safe_load is not used.

The bug was discovered 08/26/2017. The weakness was released 06/27/2018 (Website). The advisory is shared for download at github.com. This vulnerability was named CVE-2017-18342 since 06/27/2018. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 305 days. During that time the estimated underground price was around $0-$5k.

Upgrading to version 4.1 eliminates this vulnerability.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: PyYAML 4.1
Patch: github.com

Timelineinfo

08/26/2017 🔍
06/27/2018 +304 days 🔍
06/27/2018 +0 days 🔍
06/27/2018 +0 days 🔍
06/28/2018 +1 days 🔍
03/29/2023 +1735 days 🔍

Sourcesinfo

Advisory: FEDORA-2019-44643e8bcb
Status: Not defined

CVE: CVE-2017-18342 (🔍)
GCVE (CVE): GCVE-0-2017-18342
GCVE (VulDB): GCVE-100-120016

Entryinfo

Created: 06/28/2018 08:38
Updated: 03/29/2023 09:19
Changes: 06/28/2018 08:38 (59), 02/22/2020 17:50 (1), 03/29/2023 09:19 (5)
Complete: 🔍
Cache ID: 216::103

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