CVE-2026-119133

Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a memory misalignment flaw in VMContext layout that causes undefined behavior when modules contain an odd number of exception tags. A WebAssembly module with an odd tag count misaligns subsequent host fields in embedders with exceptions enabled, although no exploitation path is currently known.

CVSS v3 2.6 LOW

2.6^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p79w-pv2r-29qp
https://www.vulncheck.com/advisories/wasmtime-47.0.0-before-48.0.6-and-49.0.0-before-49.0.3-misaligned-vmcontext-via-exception-tags

Configurations

No configuration.

History

29 Oct 2026, 16:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-29 16:18

Updated : 2026-10-29 18:17

NVD link : CVE-2026-119133

Mitre link : CVE-2026-119133

CVE.ORG link : CVE-2026-119133

JSON object : View

Products Affected

No product.

CWE

CWE-758

Reliance on Undefined, Unspecified, or Implementation-Defined Behavior

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