oss-sec mailing list archives

Re: CVE Request: systemd v209+: local denial-of-service attack


From: cve-assign () mitre org
Date: Fri, 30 Sep 2016 02:52:02 -0400 (EDT)

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256

https://github.com/systemd/systemd/issues/4234
https://www.agwa.name/blog/post/how_to_crash_systemd_in_one_tweet

systemd fails an assertion in manager_invoke_notify_message when
a zero-length message is received over its notification socket.
After failing the assertion, PID 1 hangs in the pause system call.
It is no longer possible to start and stop daemons or cleanly reboot
the system. Inetd-style services managed by systemd no longer accept
connections.

Since the notification socket, /run/systemd/notify, is world-writable,
this allows a local user to perform a denial-of-service attack against
systemd.

Proof-of-concept:

        NOTIFY_SOCKET=/run/systemd/notify systemd-notify ""

Use CVE-2016-7795.


https://github.com/systemd/systemd/issues/4234#issuecomment-250441246

Older distros are affected differently I think: no assertion is
triggered but manager_dispatch_notify_fd() still returns an error
which has the bad side effect to disable the notification handler
completely

Use CVE-2016-7796.

- -- 
CVE Assignment Team
M/S M300, 202 Burlington Road, Bedford, MA 01730 USA
[ A PGP key is available for encrypted communications at
  http://cve.mitre.org/cve/request_id.html ]
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
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=XTWD
-----END PGP SIGNATURE-----


Current thread: