CVE-2026-34941 — Out-of-bounds Read in Wasmtime
Severity
6.9MEDIUMNVD
EPSS
0.0%
top 96.66%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedApr 9
Description
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 byte length of the input string when performing a bounds check. Specifically the number of code units were checked instead of the byte length, which is twice the size of the code units. This vulnerability can cause the host to read beyond the end of a WebAssembly'…
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected Packages2 packages
🔴Vulnerability Details
4VulDB▶
bytecodealliance wasmtime up to 24.0.6/36.0.6/42.0.1/44.0.0 out-of-bounds (GHSA-hx6p-xpx3-jvvv)↗2026-04-09
GHSA
▶
📋Vendor Advisories
1Red Hat▶
wasmtime: Wasmtime: Denial of Service and potential information disclosure via incorrect UTF-16 string validation↗2026-04-09
🕵️Threat Intelligence
1💬Community
2Bugzilla▶
CVE-2026-34941 wasmtime: Wasmtime: Denial of Service and potential information disclosure via incorrect UTF-16 string validation↗2026-04-09
Bugzilla▶
CVE-2026-34941 tree-sitter: Wasmtime: Denial of Service and potential information disclosure via incorrect UTF-16 string validation [fedora-all]↗2026-04-09