CVE-2026-119133 (GCVE-0-2026-119133)

Vulnerability from cvelistv5 – Published: 2026-10-29 15:58 – Updated: 2026-10-29 17:14
VLAI
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
2.1 (Low)
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
2.6 (Low)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N
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
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7818 records in the last 180 days details
References
Impacted products
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:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-10-14 00:00
Show details on NVD website
To clipboard 

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