Contract logic corruption via unclamped decimal arguments
Published Oct 5, 2021 · Updated Aug 4, 2024
Improper input validation in Vyper before 0.3.0 allows remote authenticated users to alter contract logic via decimal arguments. The external-function ABI decoder accepts out-of-range 256-bit calldata as a fixed-point decimal without inserting the required decimal clamp. A caller must invoke a deployed contract function with a decimal parameter; the accepted value can drive unintended contract decisions without directly disclosing data or interrupting the compiler.
Summary
What happened
Improper input validation in Vyper before 0.3.0 allows remote authenticated users to alter contract logic via decimal arguments. The external-function ABI decoder accepts out-of-range 256-bit calldata as a fixed-point decimal without inserting the required decimal clamp. A caller must invoke a deployed contract function with a decimal parameter; the accepted value can drive unintended contract decisions without directly disclosing data or interrupting the compiler.
The record
- CVE
- CVE-2021-41122
- Published
- Oct 5, 2021
- Updated
- Aug 4, 2024
- Vendor
- Vyper
- Product
- Vyper
- Classifications
- CWE-682
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 5, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 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?
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- Affected versionversion=< 0.3.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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