Remote code execution via unrestricted type construction
Published Dec 1, 2022 · Updated Jun 18, 2025
Unsafe deserialization in SnakeYAML before 2.0 allows context-dependent attackers to execute code through crafted YAML content. The Constructor class permits YAML type tags to instantiate arbitrary Java classes before rejecting a property whose runtime type does not match the target field. Exposure requires an embedding application to parse attacker-controlled YAML with Constructor; successful exploitation runs code with that application's privileges.
Summary
What happened
Unsafe deserialization in SnakeYAML before 2.0 allows context-dependent attackers to execute code through crafted YAML content. The Constructor class permits YAML type tags to instantiate arbitrary Java classes before rejecting a property whose runtime type does not match the target field. Exposure requires an embedding application to parse attacker-controlled YAML with Constructor; successful exploitation runs code with that application's privileges.
The record
- CVE
- CVE-2022-1471
- Published
- Dec 1, 2022
- Updated
- Jun 18, 2025
- Vendor
- SnakeYAML
- Product
- SnakeYAML
- Classifications
- CWE-20, CWE-502
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 1, 2022CVE publishedPublication date reported by the CVE source.
- Jun 18, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=2.0
What conditions does exploitation require?
What is affected?
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.
Public exploit references
- GHSA-mjmj-j48q-9wg2 proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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