Allocation of Resources Without Limits or Throttling in Wasmtime - #VU153031
Published: September 30, 2026
Vulnerability identifier: #VU153031
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-770
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to failure to enforce write allowances in wasmtime-wasi-http outgoing HTTP body write handling when a guest supplies a buffer larger than the allowance returned by check-write. A remote attacker can invoke check-write and pass an oversized buffer to write to cause a denial of service.
Affected software
Wasmtime
Remediation
Install security update from vendor's website.
Wasmtime - addressed in versions 36.0.16, 48.0.3, 49.0.1