Out-of-bounds Read in Bytecodealliance Wasmtime

CVE-2026-34941

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime contains a vulnerability where when transcoding a UTF-16 string to the latin1+utf16 component-model encoding it would incorrectly validate the byt…

Vulnerability class: Buffer Overflow

EPSS: 0.004 (29.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-34941?
CVE-2026-34941 is a high-severity vulnerability in Bytecodealliance Wasmtime, classified under Out-of-bounds Read. CVSS score: 8.1/10. Published 2026-04-09.
How severe is CVE-2026-34941?
High severity. CVSS v3 base score is 8.1 out of 10.