Dist repo call missing authorization check allowing filesystem manipulation
This is a critical security bug.
From versions 1.12.0 to 1.15.0, the Koji hub did not perform proper access
checks for the hub.distRepoMove call. By passing carefully constructed
arguments to the call, an unauthenticated user can trick Koji into moving
content around that it should not. This could result in corrupting any
files that the httpd process can write to, or revealing any files that the
httpd process can read. If the user can authenticate (at any privilege
level), then they can use this mechanism to replace a file with one that
they have uploaded.
We strongly recommend that all Koji admins implement this workaround
immediately. This workaround will effectively disable dist-repo
Because use of the hub.distRepoMove call requires a valid dist repo that
exists on disk, exploitation can be blocked by ensuring that there are
none. There are many ways this might be done. We recommend the following:
Move the repos-dist directory to another location (if it exists)
Replace it with a plain text file warning of the situation. Do not skip
$ cd /mnt/koji
$ mv repos-dist repos-dist.old
$ echo "DO NOT REMOVE. CVE-2018-1002150" > repos-dist
$ ls -l /mnt/koji/repos-dist
-rw-r--r--. 1 root root 32 Mar 19 14:35 /mnt/koji/repos-dist
When applying this workaround, make sure to take both steps. If you do not,
then the system will recreate the directory if anyone creates a new dist
Note: because code fixes can take time to deploy, we strongly recommend
that all admins apply the above workaround first. The workaround can be
easily undone once the fix is in place.
We are releasing updates for each affected version of Koji to fix this bug.
The following releases <https://pagure.io/koji/releases>
all contain the
Versions prior to 1.12.0 are not vulnerable because they do not have the
dist-repo feature. Also, the legacy-py24 branch is unaffected since it is
client-only (no hub).
For users who have customized their Koji code, we recommend rebasing your
work onto the appropriate update release. If this is not feasible, the
patch should be very easy to apply. Please see issue #850
for the code details.
As with all changes to hub code, you must restart httpd for the changes to
Fixed versions can be found at our releases page:
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