CVE-2026-119132

Wasmtime from 49.0.0 before 49.0.3 contains a denial-of-service vulnerability that allows a WebAssembly guest to trigger a host panic by transcoding overlapping strings in fused adapters. Attackers can make a same-instance component-to-component call transferring a string whose source and destination alias each other, crashing the host instead of raising a trap.

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-54p9-vhhq-8f7q
https://www.vulncheck.com/advisories/wasmtime-49.0.0-before-49.0.3-host-panic-via-overlapping-string-transcode-in-fused-adapter

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 16:18

NVD link : CVE-2026-119132

Mitre link : CVE-2026-119132

CVE.ORG link : CVE-2026-119132

JSON object : View

Products Affected

No product.

CWE

CWE-617

Reachable Assertion

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