|
Message-ID: <51F0E2D4.7040303@redhat.com> Date: Thu, 25 Jul 2013 02:33:24 -0600 From: Kurt Seifried <kseifried@...hat.com> To: oss-security@...ts.openwall.com CC: Sebastian Pipping <sebastian@...ping.org> Subject: Re: CVE request: mysecureshell: local denial of service (or worse) -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 07/23/2013 11:19 AM, Sebastian Pipping wrote: > Hello everyone, > > > mysecureshell [1] is an SFTP-only shell to be used with sshd. > > The latest release 1.31 makes use of shared memory with permissions > 666 to maintain 128 slots with one struct for each > connection/process. An unprivileged user can mark mark all > remaining slots as occupied (and optionally wait for remaining > clients to leave to block those slots, too). > > To demonstrate the issue, I have written a small command line > tool. It's free software and can be found at [2]. Use it like > this: > > # make cc -std=c99 -Wall -Wextra -pedantic local-dos.c -o > local-dos > > # ./local-dos USAGE: ./local-dos (block|unblock|show) > > # watch -n 1 -d ./local-dos block [..] > > Besides the local DoS it might be possible to attack the call to > chdir, since that is reading from shared memory, too. > > Any ideas on other attacks based on writing to that block of > shared memory? File /bin/MySecureShell is mode 4755 setuid root if > that makes it more interesting :-) > > Best, > > > > Sebastian > > > [1] http://mysecureshell.sourceforge.net/ [2] > https://github.com/hartwork/mysecureshell-issues To reiterate: so I can confirm CVE assignments, and prevent duplicate assignments you *MUST* provide links to the code commits/vulnerable code. I don't have the time to go hunting through your source code for them. People need to start making better CVE requests, or you're not going to get CVEs from me. I think if I repeat this enough times it'll work. - -- Kurt Seifried Red Hat Security Response Team (SRT) PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.13 (GNU/Linux) iQIcBAEBAgAGBQJR8OLUAAoJEBYNRVNeJnmTbEsP/jqO2hynx95cxjzC6DKkLubI t95HqOOTAdqeb9Ek3D/xHgQylvTF8tPqGc77awkLvmao17wNykBDEoS/GvvSnmMj z1UjuuPLW2jrrRnsfPbOl33XXde/3uMcTejx1feY1PvWOADM/rElvDob7+9tXnUI CFivq/ibMqTjKdA7uOMMkSTZ96w0oIXVnAbPUm4u2vc6imY8CEMGhXwNrlm+7jwa hykaJjpnTvXScfqcpORcEJGNRojrnCa9LhVid9hOkvDaSiuB7zVgYgyqkc0tLGXa +zkEXKcrWlC4OuuRvCFZ2UvkBmK46OTkNyAmaRhxji2/PezRAqCThH0gPZk69LQb 7YmonMCOJtqXVV6DtJ4G3dIg3i/VZvgpQC6IoaH2VKKYK9I5ThTYPApRclWXLPJ7 bZnpe2MgeGfbOVRB6/ydozEuPK+9CgSzWl2ShLuRQfbFyV/3I4jIpMJKINULMTbx CTtVHpN4G6VhK+5A97mJMYBSKxFbqPOm/tF2RNSDaMpF285oMLnPs8Rq5EU4NLwj 3awuvmSu0UmDoAv/Pw/n+pPxWjgG45coGOICujaIQdh4iOoHcMM010P8JSxPaLZ7 uPaG7SSdkiCK22RhS3MGX+T+qiF1jXRSEcZB/g6kHVh/FSApzmmfuSRlR1uzompH hmNA9OuY7vOtfqBgQ/dB =kgXF -----END PGP SIGNATURE-----
Powered by blists - more mailing lists
Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.