Prototype pollution via unchecked nested property keys
Published Apr 4, 2025 · Updated Apr 4, 2025
Prototype pollution in Jon Schlinkert expand-object 0.4.2 and earlier allows remote attackers to alter object prototypes via crafted input. The expand() function in index.js writes attacker-selected nested properties without rejecting the sensitive proto key. Exploitation requires a consuming application to pass attacker-controlled strings to expand(); successful input can pollute properties inherited by other objects, altering application data or behavior.
Summary
What happened
Prototype pollution in Jon Schlinkert expand-object 0.4.2 and earlier allows remote attackers to alter object prototypes via crafted input. The expand() function in index.js writes attacker-selected nested properties without rejecting the sensitive proto key. Exploitation requires a consuming application to pass attacker-controlled strings to expand(); successful input can pollute properties inherited by other objects, altering application data or behavior.
The record
- CVE
- CVE-2025-3197
- Published
- Apr 4, 2025
- Updated
- Apr 4, 2025
- Vendor
- Jon Schlinkert
- Product
- expand-object
- Classifications
- CWE-1321
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 4, 2025CVE publishedPublication date reported by the CVE source.
- Apr 4, 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?
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- Affected versionversion=0.0.0 <*
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- expand-object prototype-pollution proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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