Use of uninitialized resource in Wasmtime - #VU153231
Published: October 3, 2026
Vulnerability identifier: #VU153231
CSH Severity: Low
CVSS v4: 2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-908
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to disclose sensitive information.
The vulnerability exists due to use of an uninitialized resource in the WASIp1 `fd_readdir` implementation when listing entries from a preopened directory. A remote user can invoke `fd_readdir` to disclose sensitive information.
The affected guest must have access to a preopened directory, and user interaction is required.
Affected software
Wasmtime
Remediation
Install security update from vendor's website.
Wasmtime - addressed in versions 36.0.17, 48.0.4, 49.0.2