Sandbox breakout bug (details omitted)

[hx1997]

What happened?

The details of this bug have been sent to @DavidXanatos by email on March 21. This issue only serves to track the fixing (that is, if this is confirmed to be a real bug) progress publicly.

In short, I've found a bug in Sandboxie that presumably lets an attacker break out of the sandbox. This has yet to be confirmed by the developers, though.

To Reproduce

Described in the email.

Expected behavior

Sandboxed programs should not be allowed to escape.

What is your Windows edition and version?

Windows 10 Home 20H2 (19042.1466) 64-bit

In which Windows account you have this problem?

A local or Microsoft account without special changes.

Please mention any installed security software

Built-in realtime protection in Windows 10

What version of Sandboxie are you running?

Sandboxie Classic v5.55.13 64-bit

Is it a regression?

No response

List of affected browsers

No response

In which sandbox type you have this problem?

I only reproduced it with Sandboxie Classic.

Is the sandboxed program also installed outside the sandbox?

No, it is not installed in the real system.

Can you reproduce this problem on an empty sandbox?

I can confirm it also on an empty sandbox.

Did you previously enable some security policy settings outside Sandboxie?

No response

Crash dump

No response

Trace log

No response

Sandboxie.ini configuration

No response

Sandboxie-Plus.ini configuration (for Plus interface issues)

No response

[DavidXanatos]

I can confirm the issue and luckily there is already a workaround in place which can be enabled, by adding
EnableObjectFiltering=y to the [GlobalSettings] section in the sandboxie.ini
or through the UI:

never the less the issue when not using this enhanced filtering is present and will be fixed ...