Improper input validation in Bytecodealliance Wasmtime
CVE-2026-115384
Wasmtime 39.0.0 before 48.0.4 and 49.0.0 before 49.0.2 contains a stack buffer overflow vulnerability that allows malicious guests to write ~16KB to the native stack via unvalidated async callback result types. Attackers can supply components with mistyped component-model-async callback functions to overwrite return addresses, crashing the host or escaping the sandbox.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/bytecodealliance/wasmtime/security/advisories/GHSA-32h6-97mm-8q3c (vendor-advisory)
- www.vulncheck.com/advisories/wasmtime-39.0.0-before-48.0.4-and-49.0.0-before-49… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-115384?
- CVE-2026-115384 is a critical-severity vulnerability in Bytecodealliance Wasmtime, classified under Improper Input Validation. CVSS score: 9.9/10. Published 2026-10-22.
- How severe is CVE-2026-115384?
- Critical severity. CVSS v3 base score is 9.9 out of 10.