CVE-2021-29511

Memory over-allocation in evm crate

MEDIUM
6.5
CVSS Score
Published: May 12, 2021 at 05:15 PM UTC
Updated: June 17, 2026 at 03:47 AM UTC
2 products affected across 2 vendorsEvmProject Evm

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Severity
MEDIUM6.5
Exploit prediction
EPSS 1%

Description

evm is a pure Rust implementation of Ethereum Virtual Machine. Prior to the patch, when executing specific EVM opcodes related to memory operations that use `evm_core::Memory::copy_large`, the `evm` crate can over-allocate memory when it is not needed, making it possible for an attacker to perform denial-of-service attack. The flaw was corrected in commit `19ade85`. Users should upgrade to `==0.21.1, ==0.23.1, ==0.24.1, ==0.25.1, >=0.26.1`. There are no workarounds. Please upgrade your `evm` crate version.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Affected range stops below 0.21.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

6.5MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-770CWE-787

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