CVE-2026-115383

Wasmtime 47.0.0 before 48.0.4 and 49.0.0 before 49.0.2 contains an improper validation vulnerability that accepts components whose core modules import WebAssembly tags with a subtype of the original type. Malicious guests can mis-type exception object payloads to corrupt the GC heap, causing Wasmtime to panic when the exceptions proposal is enabled.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

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-cfhf-m2cr-62wj
https://www.vulncheck.com/advisories/wasmtime-47.0.0-before-48.0.4-and-49.0.0-before-49.0.2-gc-heap-corruption-via-tag-imports

Configurations

No configuration.

History

22 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 19:17

Updated : 2026-10-22 19:17

NVD link : CVE-2026-115383

Mitre link : CVE-2026-115383

CVE.ORG link : CVE-2026-115383

JSON object : View

Products Affected

No product.

CWE

CWE-1287

Improper Validation of Specified Type of Input

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