CVE-2023-42441

Vyper has incorrect re-entrancy lock when key is empty string

MEDIUM
5.3
CVSS Score
Published: September 18, 2023 at 08:19 PM UTC
Updated: June 17, 2026 at 06:23 AM UTC
1 product affected across 1 vendorVyper

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine (EVM). Starting in version 0.2.9 and prior to version 0.3.10, locks of the type `@nonreentrant("")` or `@nonreentrant('')` do not produce reentrancy checks at runtime. This issue is fixed in version 0.3.10. As a workaround, ensure the lock name is a non-empty string.

Affected

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

v < 0.3.100.2.9 ≤ v < 0.3.100.2.9
Affected range stops below 0.3.10, 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:

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-833CWE-667

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