Description
Wasmtime from 49.0.0 before 49.0.3 contains a denial-of-service vulnerability that allows a WebAssembly guest to trigger a host panic by transcoding overlapping strings in fused adapters. Attackers can make a same-instance component-to-component call transferring a string whose source and destination alias each other, crashing the host instead of raising a trap.
References2
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H - CVSS 4.0
-
5.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/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: 11 · as of 2 November 2026
- CWE
- CWE-617
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.