Bug 2559235 (CVE-2026-115383)

Summary: CVE-2026-115383 wasmtime: wasmtime: Denial of Service via improper validation of WebAssembly tag imports
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Wasmtime. This vulnerability allows an untrusted guest module to cause a Denial of Service (DoS) by triggering a host application crash. When the WebAssembly exceptions feature is enabled, Wasmtime improperly validates imported tags that use subtypes of expected types. A malicious guest can exploit this behavior to mis-type exception payloads and corrupt internal memory, causing the runtime to terminate abruptly.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-10-22 19:25:01 UTC
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.