[CVE-2022-30123] Possible shell escape sequence injection vulnerability in Rack
Aaron Patterson
There is a possible shell escape sequence injection vulnerability in the Lint
and CommonLogger components of Rack. This vulnerability has been assigned the
CVE identifier CVE-2022-30123.
Versions Affected: All.
Not affected: None
Fixed Versions: 2.0.9.1, 2.1.4.1, 2.2.3.1
Impact
------
Carefully crafted requests can cause shell escape sequences to be written to
the terminal via Rack's Lint middleware and CommonLogger middleware. These
escape sequences can be leveraged to possibly execute commands in the victim's
terminal.
Impacted applications will have either of these middleware installed, and
vulnerable apps may have something like this:
```
use Rack::Lint
```
Or
```
use Rack::CommonLogger
```
All users running an affected release should either upgrade or use one of the
workarounds immediately.
Releases
--------
The FIXED releases are available at the normal locations.
Workarounds
-----------
Remove these middleware from your application
Patches
-------
To aid users who aren't able to upgrade immediately we have provided patches for
the two supported release series. They are in git-am format and consist of a
single changeset.
* 2-0-shell-escape.patch - Patch for 2.0 series
* 2-1-shell-escape.patch - Patch for 2.1 series
* 2-2-shell-escape.patch - Patch for 2.2 series
Credits
-------
Thanks to [@vairelt](https://hackerone.com/vairelt) for reporting this