Description
Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 caps component-model resource handle tables only per component instance and does not charge handle allocations to any ResourceLimiter or StoreLimits. A malicious guest can repeatedly call resource.new and instantiate sub-components to exceed the per-instance cap many times over, causing unbounded host memory growth.
References2
Metrics
- CVSS 3.1
-
6.2
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 4 · as of 3 November 2026
- CWE
- CWE-770
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