CVE-2026-34944

Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, On x86-64 platforms with SSE3 disabled Wasmtime's compilation of the f64x2.splat WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but this data is not visible to WebAssembly guests. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.

CVSS v3 5.7 MEDIUM

5.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.1 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-qqfj-4vcm-26hv	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:bytecodealliance:wasmtime::::::rust::*
	cpe:2.3:a:bytecodealliance:wasmtime::::::rust::*
	cpe:2.3:a:bytecodealliance:wasmtime::::::rust::*
	cpe:2.3:a:bytecodealliance:wasmtime::::::rust::*

History

20 Apr 2026, 18:27

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.7
First Time		Bytecodealliance Bytecodealliance wasmtime
References	~~() https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-qqfj-4vcm-26hv -~~	() https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-qqfj-4vcm-26hv - Vendor Advisory
CPE		cpe:2.3:a:bytecodealliance:wasmtime::::::rust::*

09 Apr 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-09 19:16

Updated : 2026-04-20 18:27

NVD link : CVE-2026-34944

Mitre link : CVE-2026-34944

CVE.ORG link : CVE-2026-34944

JSON object : View

Products Affected

bytecodealliance

wasmtime

CWE

CWE-248

Uncaught Exception

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