All vulnerabilities
CVE-2026-118688GHSA-m9f7-9w4p-gv38

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

bytecodealliance wasmtime
Open in ThreatlineRecord JSON
CVSS
8.8High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
Fixed in36.0.18Also 48.0.6, 49.0.3CVE List
Published28 Oct 2026Updated 28 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Reports 1

1 outlet mention it. Reports are not confirmation; each links to its source.

Description

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.

Text from CVE List

Affected versions 6

  • wasmtimeaffected: all versions before 36.0.18CVE List
  • wasmtimeunaffected: 36.0.18CVE List
  • wasmtimeaffected: 37.0.0 before 48.0.6CVE List
  • wasmtimeunaffected: 48.0.6CVE List
  • wasmtimeaffected: 49.0.0 before 49.0.3CVE List
  • wasmtimeunaffected: 49.0.3CVE List

References 2