Low severity · published Oct 22, 2026
CVE-2026-115393
Wasmtime before 24.0.12, 25.0.0 before 36.0.13, 37.0.0 before 46.0.2, and 47.0.0 before 47.0.3 Cross-Engine Type Confusion
New
3.8
CVSS
0.1%
EPSS
No
On KEV
Description
Wasmtime before 24.0.12, 25.0.0 before 36.0.13, 37.0.0 before 46.0.2, and 47.0.0 before 47.0.3 contains a type confusion vulnerability because several Store APIs fail to validate that objects belong to the Store's Engine. Embedders mixing objects between Engines via Instance::new, StructRefPre::new, or Tag::new can trigger trampoline signature mismatches causing out-of-bounds stack writes, GC heap corruption, or panics.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:L/I:L/A:L
Attack vector
Local
Complexity
High
Privileges
High
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 0% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WA
wasmtime · bytecodealliance
before 24.0.12; 25.0.0 before 36.0.13; 37.0.0 before 46.0.2; 47.0.0 before 47.0.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-115393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-115393
github.com
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-hgjw-h833-99q9
www.vulncheck.com
https://www.vulncheck.com/advisories/wasmtime-before-24.0.12-25.0.0-before-36.0.13-37.0.0-before-46.0.2-and-47.0.0-before-47.0.3-cross-engine-type-confusion
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