GHSA-JXHV-7H78-9775 Wasmtime: Panic when transcoding misaligned utf-16 strings

Impact Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be passed to the host for transcoding which would trigger a host panic. This panic ...

Wasmtime: Heap OOB read in component model UTF-16 to latin1+utf16 string transcoding

Summary 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...

GHSA-HX6P-XPX3-JVVV Wasmtime: Heap OOB read in component model UTF-16 to latin1+utf16 string transcoding

Summary 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...

DEBIAN-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 byte length of the input string when performing a bounds chec...

DEBIAN-CVE-2026-34942

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be...

UBUNTU-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 byte length of the input string when performing a bounds chec...

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 byte length of the input string when performing a bounds chec...

CVE-2026-34942 Wasmtime panics when transcoding misaligned utf-16 strings

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be...

CVE-2026-34942 Wasmtime panics when transcoding misaligned utf-16 strings

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be...

CVE-2026-34942

Wasmtime VM exposes a DoS risk due to a panic-triggering path when transcoding strings into utf16/latin1+utf16. Root cause: alignment verification for reallocated strings was improper, allowing unaligned pointers to be passed to the host by a malicious guest. Affected versions prior to fixed rele...

CVE-2026-34942 Wasmtime panics when transcoding misaligned utf-16 strings

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be...

CVE-2026-34942

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, Wasmtime's implementation of transcoding strings into the Component Model's utf16 or latin1+utf16 encodings improperly verified the alignment of reallocated strings. This meant that unaligned pointers could be...

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 byte length of the input string when performing a bounds chec...

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 byte length of the input string when performing a bounds chec...

CVE-2026-34941 Wasmtime has a Heap OOB read in component model UTF-16 to latin1+utf16 string transcoding

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 chec...

CVE-2026-34941

Wasmtime (WebAssembly runtime) contains a heap OOB read during transcoding of UTF-16 to the latin1+utf16 component-model encoding. The bug stems from validating the input length by code units instead of by byte length, causing reads beyond the WebAssembly linear memory during bounds checking. In ...

CVE-2026-34941 Wasmtime has a Heap OOB read in component model UTF-16 to latin1+utf16 string transcoding

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 chec...

RUSTSEC-2026-0093 Heap OOB read in component model UTF-16 to latin1+utf16 string transcoding

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-hx6p-xpx3-jvvv For more information see the GitHub-hosted security advisory...

RUSTSEC-2026-0092 Panic when transcoding misaligned component model UTF-16 strings

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-jxhv-7h78-9775 For more information see the GitHub-hosted security advisory...

PT-2026-31680

Name of the Vulnerable Software and Affected Versions Wasmtime versions prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1 Description Wasmtime contains an issue where transcoding a UTF-16 string to the latin1+utf16 component-model encoding incorrectly validates the byte length of the input string durin...