High severity · published May 14, 2026
CVE-2026-44216
Wasmtime: Panic when allocating a table exceeding the size of the host's address space
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WA
wasmtime · bytecodealliance
>= 30.0.0, < 36.0.8; >= 37.0.0, < 43.0.2; 44.0.0 · source: vendor, NVD
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44216
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44216
Mitigation
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:45341
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-44216
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2477467
security.access.redhat.com
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44216.json
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