CVE-2026-119133 (GCVE-0-2026-119133)
Vulnerability from cvelistv5 – Published: 2026-10-29 15:58 – Updated: 2026-10-29 17:14
VLAI
EPSS
VEX
Title
Wasmtime 47.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Misaligned VMContext via Exception Tags
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-29 16:16 UTC
CWE
- CWE-758 - Reliance on Undefined, Unspecified, or Implementation-Defined Behavior
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/bytecodealliance/wasmtime/secu… | vendor-advisory |
| https://www.vulncheck.com/advisories/wasmtime-47.… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| bytecodealliance | wasmtime |
Affected:
47.0.0 , < 48.0.6
(semver)
Unaffected: 48.0.6 (semver) Affected: 49.0.0 , < 49.0.3 (semver) Unaffected: 49.0.3 (semver) cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:* cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:* |
Date Public
2026-10-14 00:00
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