wasmtime-wasi-http in Wasmtime before 36.0.16, 37.0.0 before 48.0.3, and 49.0.0 before 49.0.1 does not enforce the wasi:io/streams check-write allowance for WASIp2 outgoing HTTP bodies, so oversized writes succeed instead of trapping. A malicious guest can pass large buffers to write on outgoing-body resources, holding host allocations for the store's lifetime and exhausting host memory.
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-c9gc-w9vx-w86p
Published: 2026-10-22
Updated: 2026-10-22
Base Score: 4.9
Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C
Severity: Medium
Base Score: 6.2
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: Medium
Base Score: 6.9
Vector: 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
Severity: Medium