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.
History

Wed, 10 Dec 2025 21:30:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:wasmi-labs:wasmi:*:*:*:*:*:rust:*:*
cpe:2.3:a:wasmi-labs:wasmi:1.0.0:*:*:*:*:rust:*:*

Tue, 09 Dec 2025 16:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 09 Dec 2025 10:15:00 +0000

Type Values Removed Values Added
First Time appeared Wasmi-labs
Wasmi-labs wasmi
Vendors & Products Wasmi-labs
Wasmi-labs wasmi

Tue, 09 Dec 2025 03:15:00 +0000

Type Values Removed Values Added
Description 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.
Title Wasmi's Linear Memory has a Critical Use After Free Vulnerability
Weaknesses CWE-416
References
Metrics cvssV3_1

{'score': 8.4, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2025-12-09T02:52:46.938Z

Updated: 2025-12-09T15:21:18.048Z

Reserved: 2025-12-05T15:42:44.715Z

Link: CVE-2025-66627

cve-icon Vulnrichment

Updated: 2025-12-09T15:21:13.267Z

cve-icon NVD

Status : Analyzed

Published: 2025-12-09T16:18:21.910

Modified: 2025-12-10T21:16:04.107

Link: CVE-2025-66627

cve-icon Redhat

No data.