UNIX symbolic link following in Wasmtime - #VU144568
Published: August 21, 2026
Vulnerability identifier: #VU144568
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-61
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to access files and directories outside the intended filesystem sandbox.
The vulnerability exists due to unix symbolic link following in wasmtime-wasi filesystem sandboxing when processing paths or symlinks containing trailing slashes. A remote user can provide a crafted path or symlink reference to access files and directories outside the intended filesystem sandbox.
This issue does not affect environments using a Linux kernel newer than 5.6 with the openat2 syscall and the RESOLVE_BENEATH flag.
Affected software
Wasmtime
Remediation
Install security update from vendor's website.
Wasmtime - addressed in versions 24.0.13, 36.0.14, 46.0.3, 47.0.4