Host panic via oversized memory64 table allocation
Published May 14, 2026 · Updated May 14, 2026
Table-allocation overflow in Bytecode Alliance Wasmtime allows remote authenticated users to crash the host with a crafted WebAssembly module. The on-demand instance allocator computes an untrusted memory64 table allocation size with checked arithmetic and panics when that calculation overflows. Exploitation requires the default on-demand allocator and enabled memory64 feature; the pooling allocator is not affected.
Summary
What happened
Table-allocation overflow in Bytecode Alliance Wasmtime allows remote authenticated users to crash the host with a crafted WebAssembly module. The on-demand instance allocator computes an untrusted memory64 table allocation size with checked arithmetic and panics when that calculation overflows. Exploitation requires the default on-demand allocator and enabled memory64 feature; the pooling allocator is not affected.
The record
- CVE
- CVE-2026-44216
- Published
- May 14, 2026
- Updated
- May 14, 2026
- Vendor
- Bytecode Alliance
- Product
- Wasmtime
- Classifications
- T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 14, 2026CVE publishedPublication date reported by the CVE source.
- May 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 30.0.0, < 36.0.8
- Affected versionversion=>= 37.0.0, < 43.0.2
- Affected versionversion=44.0.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo