CVE-2026-115391

Wasmtime 46.0.0 before 46.0.3 and 47.0.0 before 47.0.4 contains an uncontrolled resource allocation vulnerability in its WASIp3 implementation that buffers guest-specified-length writes on the host without limit. Malicious guests can offer large buffers to WASIp3 file or HTTP write streams, causing the host to copy and buffer all bytes, bounded only by guest linear memory, exhausting host memory.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.3 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-x84v-gj2h-g759
https://www.vulncheck.com/advisories/wasmtime-46.0.0-before-46.0.3-and-47.0.0-before-47.0.4-unbounded-heap-allocation-via-wasip3-streams

Configurations

No configuration.

History

22 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 19:17

Updated : 2026-10-22 19:17

NVD link : CVE-2026-115391

Mitre link : CVE-2026-115391

CVE.ORG link : CVE-2026-115391

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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