Allocation of Resources Without Limits or Throttling in Wasmtime - #VU155843
Published: October 15, 2026
Vulnerability identifier: #VU155843
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 allocation of resources without store-wide limits in Wasmtime's component-model handle tables when processing guest resource allocations. A remote attacker can repeatedly instantiate a sub-component and allocate resource handles to cause a denial of service.
Exploitation is possible with the default configuration and requires no linear memory, core tables, or host imports. Handle-table allocations are not charged to ResourceLimiter or StoreLimits.
Affected software
Wasmtime
Remediation
Install security update from vendor's website.
Wasmtime - addressed in versions 36.0.18, 48.0.6, 49.0.3