Tmp files readable by other users in sync-exec

Affected versions of sync-exec use files located in /tmp/ to buffer command results before returning values. As /tmp/ is almost always set with world readable permissions, this may allow low privilege users on the system to read the results of commands run via sync-exec under a higher privilege user.

Recommendation

There is currently no direct patch for sync-exec, as the child_process.execSync function provided in Node.js v0.12.0 and later provides the same functionality natively.

The best mitigation currently is to update to Node.js v0.12.0 or later, and migrate all uses of sync-exec to child_process.execSync().