CVE-2025-66627
December 09, 2025
Wasmi is a WebAssembly interpreter focused on constrained and embedded systems. In versions 0.41.0, 0.41.1, 0.42.0 through 0.47.1, 0.50.0 through 0.51.2 and 1.0.0, Wasmi's linear memory implementation leads to a Use After Free vulnerability, triggered by a WebAssembly module under certain memory growth conditions. This issue potentially leads to memory corruption, information disclosure, or code execution. This issue is fixed in versions 0.41.2, 0.47.1, 0.51.3 and 1.0.1. To workaround this issue, consider limiting the maximum linear memory sizes where feasible.
Affected Packages
https://github.com/wasmi-labs/wasmi.git (GITHUB):
Affected version(s) =v1.0.0 <v1.0.1Fix Suggestion:
Update to version v1.0.1https://github.com/wasmi-labs/wasmi.git (GITHUB):
Affected version(s) >=v0.41.0 <0.41.2Fix Suggestion:
Update to version 0.41.2https://github.com/wasmi-labs/wasmi.git (GITHUB):
Affected version(s) >=v0.42.0 <v0.47.1Fix Suggestion:
Update to version v0.47.1https://github.com/wasmi-labs/wasmi.git (GITHUB):
Affected version(s) >=v0.50.0 <v0.51.3Fix Suggestion:
Update to version v0.51.3wasmi (RUST):
Affected version(s) =1.0.0 <1.0.1Fix Suggestion:
Update to version 1.0.1wasmi (RUST):
Affected version(s) >=0.50.0 <0.51.3Fix Suggestion:
Update to version 0.51.3wasmi (RUST):
Affected version(s) >=0.42.0 <0.47.1Fix Suggestion:
Update to version 0.47.1wasmi (RUST):
Affected version(s) >=0.41.0 <0.41.2Fix Suggestion:
Update to version 0.41.2Related ResourcesĀ (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.6
Attack Vector
LOCAL
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
8.4
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Use After Free
EPSS
Base Score:
0.02