8.4
HIGH CVSS 3.1
CVE-2025-66627
Wasmi's Linear Memory has a Critical Use After Free Vulnerability
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.

INFO

Published Date :

Dec. 9, 2025, 4:18 p.m.

Last Modified :

Dec. 9, 2025, 6:36 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2025-66627 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Wasmi-labs wasmi
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
Solution
Update Wasmi to a patched version or limit linear memory sizes.
  • Update Wasmi to version 0.41.2 or later.
  • Update Wasmi to version 0.47.2 or later.
  • Update Wasmi to version 0.51.3 or later.
  • Update Wasmi to version 1.0.1 or later.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2025-66627.

URL Resource
https://github.com/wasmi-labs/wasmi/security/advisories/GHSA-g4v2-cjqp-rfmq
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-66627 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-66627 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-66627 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-66627 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Dec. 09, 2025

    Action Type Old Value New Value
    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.
    Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-416
    Added Reference https://github.com/wasmi-labs/wasmi/security/advisories/GHSA-g4v2-cjqp-rfmq
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 8.4
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact