by Kastro
Paper/Archive/CVE-2026-115384

CVE-2026-115384

bytecodealliance wasmtime — Wasmtime 39.0.0 before 48.0.4 and 49.0.0 before 49.0.2 Stack Buffer Overflow

EPSS 0.3%CVSS 9.9
critical.is priorityof 100
35
CVSS 9.9 (CNA)9.9 / 10 × 3029.7Not in CISA KEV+300.0EPSS percentile 24.0.240 × 204.8No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
wasmtime39.0.0 – < 48.0.448.0.4CNA
wasmtime49.0.0 – < 49.0.249.0.2CNA

Scores by source

VulnCheck (CNA)9.9CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
VulnCheck (CNA)9.4CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

advisorygithub.com/bytecodealliance/wasmtime/security/advisories/GHSA-32h6-97mm-8q3cwriteupvulncheck.com/advisories/wasmtime-39.0.0-before-48.0.4-and-49.0.0-before-49.0.2-stack-buffer-overflow