Remote code execution via unsafe YAML deserialization
Published Feb 19, 2020 · Updated Aug 5, 2024
Unsafe deserialization in ruamel.yaml 0.16.7 and earlier allows remote attackers to execute arbitrary code through untrusted YAML input. The top-level load() method accepts Python-specific YAML object tags and constructs attacker-selected objects or callables instead of restricting input to basic data types. The application must pass attacker-controlled data to load(); successful exploitation runs code with the application process privileges.
Summary
What happened
Unsafe deserialization in ruamel.yaml 0.16.7 and earlier allows remote attackers to execute arbitrary code through untrusted YAML input. The top-level load() method accepts Python-specific YAML object tags and constructs attacker-selected objects or callables instead of restricting input to basic data types. The application must pass attacker-controlled data to load(); successful exploitation runs code with the application process privileges.
The record
- CVE
- CVE-2019-20478
- Published
- Feb 19, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- Unavailable
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 19, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
No sourced classifications are available.
Public exploit references
- Exploit-DB 47655 proof of conceptproof of concept · unverified
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Technologies
Your stack
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Your stack
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