Prototype pollution via array-wrapped __proto__ path
Published Jan 28, 2022 · Updated Sep 16, 2024
Prototype pollution in bmoor before 0.10.1 allows remote attackers to modify object prototypes through crafted property paths. The set function compares path elements against blocked property names without first coercing array-wrapped elements to strings, so an array containing proto bypasses the denylist and writes to Object.prototype. Exploitation requires a consuming application to pass an attacker-controlled path to set; polluted inherited properties can alter application data or behavior, and the exact consequence depends on how the application uses them.
Summary
What happened
Prototype pollution in bmoor before 0.10.1 allows remote attackers to modify object prototypes through crafted property paths. The set function compares path elements against blocked property names without first coercing array-wrapped elements to strings, so an array containing proto bypasses the denylist and writes to Object.prototype. Exploitation requires a consuming application to pass an attacker-controlled path to set; polluted inherited properties can alter application data or behavior, and the exact consequence depends on how the application uses them.
The record
- CVE
- CVE-2021-23558
- Published
- Jan 28, 2022
- Updated
- Sep 16, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-1321
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 28, 2022CVE publishedPublication date reported by the CVE source.
- Sep 16, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- Snyk bmoor 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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