CVE-2026-119140

Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains a denial of service vulnerability that allows malicious components to panic the host via thread.yield in start functions. Attackers can supply a component whose start function calls an async-lowered import then thread.yield, causing an undisposed fiber drop that crashes embedders.

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-5hhx-4wrr-3j9g
https://www.vulncheck.com/advisories/wasmtime-46.0.0-before-48.0.6-and-49.0.0-before-49.0.3-host-panic-via-thread-yield

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-2026-119140

Mitre link : CVE-2026-119140

CVE.ORG link : CVE-2026-119140

JSON object : View

Products Affected

No product.

CWE

CWE-372

Incomplete Internal State Distinction

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