CVE-2026-115381
Published:October 22, 2026
Updated:October 23, 2026
Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an unbounded memory allocation in the wasmtime-wasi WASIp2 write-zeroes method of SinkOutputStream, the default stream used when stdout/stderr are not configured. A malicious WebAssembly guest can request huge zero-filled writes, exhausting host memory and causing denial of service.
Affected Packages
https://github.com/bytecodealliance/wasmtime.git (GITHUB):
Affected version(s) >=v36.0.0 <v36.0.17Fix Suggestion:
Update to version v36.0.17https://github.com/bytecodealliance/wasmtime.git (GITHUB):
Affected version(s) >=v49.0.0 <v49.0.2Fix Suggestion:
Update to version v49.0.2https://github.com/bytecodealliance/wasmtime.git (GITHUB):
Affected version(s) >=v48.0.0 <v48.0.4Fix Suggestion:
Update to version v48.0.4wasmtime-wasi (RUST):
Affected version(s) >=36.0.0 <36.0.17Fix Suggestion:
Update to version 36.0.17wasmtime-wasi (RUST):
Affected version(s) >=48.0.0 <48.0.4Fix Suggestion:
Update to version 48.0.4wasmtime-wasi (RUST):
Affected version(s) >=49.0.0 <49.0.2Fix Suggestion:
Update to version 49.0.2Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.9
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
LOW
User Interaction
PASSIVE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.8
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Allocation of Resources Without Limits or Throttling