CVE-2026-115386

Wasmtime before 36.0.17, 37.0.0 before 48.0.4, and 49.0.0 before 49.0.2 contains an information disclosure vulnerability in the WASIp1 fd_readdir implementation that copies uninitialized struct padding into guest memory. Guests with a preopened directory can list entries to receive three bytes of leftover host stack or heap memory per directory entry.

CVSS v3 2.6 LOW

2.6^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-96f6-r43r-8c24
https://www.vulncheck.com/advisories/wasmtime-before-36.0.17-37.0.0-before-48.0.4-and-49.0.0-before-49.0.2-memory-disclosure-via-fd-readdir

Configurations

No configuration.

History

22 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 19:17

Updated : 2026-10-23 15:17

NVD link : CVE-2026-115386

Mitre link : CVE-2026-115386

CVE.ORG link : CVE-2026-115386

JSON object : View

Products Affected

No product.

CWE

CWE-908

Use of Uninitialized Resource

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