What is CVE-2025-66627?

CVE-2025-66627 is a high-severity vulnerability in Wasmi-labs Wasmi, classified under Use After Free. CVSS score: 8.4/10. Published 2025-12-09.

How severe is CVE-2025-66627?

High severity. CVSS v3 base score is 8.4 out of 10.

Use After Free in Wasmi-labs Wasmi

CVE-2025-66627

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 vulnerabilit…

Vulnerability class: Use-After-Free

EPSS: 0.001 (2.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.4 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Wasmi-labs Wasmi — versions >= 0.42.0, < 0.47.1, 1.0.0, >= 0.41.0, < 0.41.2

Weakness classification (CWE)

CWE-416 — Use After Free

References

security-advisories@github.com (x_refsource_CONFIRM, Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2025-66627?: CVE-2025-66627 is a high-severity vulnerability in Wasmi-labs Wasmi, classified under Use After Free. CVSS score: 8.4/10. Published 2025-12-09.
How severe is CVE-2025-66627?: High severity. CVSS v3 base score is 8.4 out of 10.