CVE-2026-44216

Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg	Mitigation 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:44.0.0:::::rust::

History

18 May 2026, 13:36

Type	Values Removed	Values Added
CPE		cpe:2.3:a:bytecodealliance:wasmtime::::::rust::* cpe:2.3:a:bytecodealliance:wasmtime:44.0.0:::::rust::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
First Time		Bytecodealliance wasmtime Bytecodealliance
References	~~() https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg -~~	() https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg - Mitigation, Vendor Advisory

14 May 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-14 15:16

Updated : 2026-05-18 13:36

NVD link : CVE-2026-44216

Mitre link : CVE-2026-44216

CVE.ORG link : CVE-2026-44216

JSON object : View

Products Affected

bytecodealliance

wasmtime

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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