CVE-2026-118688

wasmtime-wasi in Wasmtime before 36.0.18, 37.0.0 before 48.0.6, and 49.0.0 before 49.0.3 re-appends a trailing slash to rename source paths, causing renameat on macOS and FreeBSD hosts to follow directory symlinks. A guest with sandbox write access can rename a relative symlink such as "up/" to move host directories into its sandbox and read or write them.

CVSS v3 7.9 HIGH

7.9^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.3 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-m9f7-9w4p-gv38
https://www.vulncheck.com/advisories/wasmtime-before-36.0.18-37.0.0-before-48.0.6-and-49.0.0-before-49.0.3-sandbox-escape-via-symlink-rename

Configurations

No configuration.

History

28 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-28 19:17

Updated : 2026-10-28 19:17

NVD link : CVE-2026-118688

Mitre link : CVE-2026-118688

CVE.ORG link : CVE-2026-118688

JSON object : View

Products Affected

No product.

CWE

CWE-61

UNIX Symbolic Link (Symlink) Following

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