Prototype pollution via __proto__ XML names
Published Dec 12, 2023 · Updated Aug 2, 2024
Prototype pollution in fast-xml-parser before 4.1.2 allows remote authenticated users to alter JavaScript object prototypes via crafted XML tag or attribute names. The XMLParser.parse routine accepts proto as a tag or attribute and writes nested properties onto the object prototype, such as polluted. Exploitation requires access to an application that parses attacker-controlled XML; prototype changes can disclose data or enable downstream gadget abuse, while this record does not establish direct code execution.
Summary
What happened
Prototype pollution in fast-xml-parser before 4.1.2 allows remote authenticated users to alter JavaScript object prototypes via crafted XML tag or attribute names. The XMLParser.parse routine accepts proto as a tag or attribute and writes nested properties onto the object prototype, such as polluted. Exploitation requires access to an application that parses attacker-controlled XML; prototype changes can disclose data or enable downstream gadget abuse, while this record does not establish direct code execution.
The record
- CVE
- CVE-2023-26920
- Published
- Dec 12, 2023
- Updated
- Aug 2, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-1321
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 12, 2023CVE publishedPublication date reported by the CVE source.
- Aug 2, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
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Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- fast-xml-parser __proto__ XML parser proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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