CVE-2026-115388

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.

CVSS v3 6.2 MEDIUM

6.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.5 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-c9gc-w9vx-w86p
https://www.vulncheck.com/advisories/wasmtime-before-36.0.16-37.0.0-before-48.0.3-and-49.0.0-before-49.0.1-memory-exhaustion-dos-via-wasmtime-wasi-http-outgoing-body-write

Configurations

No configuration.

History

22 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 19:17

Updated : 2026-10-29 04:18

NVD link : CVE-2026-115388

Mitre link : CVE-2026-115388

CVE.ORG link : CVE-2026-115388

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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