Bug 293081 (CVE-2007-5201) - CVE-2007-5201 Duplicity discloses password in FTP backend
Summary: CVE-2007-5201 Duplicity discloses password in FTP backend
Alias: CVE-2007-5201
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact: Fedora Extras Quality Assurance
URL: http://bugs.debian.org/cgi-bin/bugrep...
Depends On: 362821 362831 362841
TreeView+ depends on / blocked
Reported: 2007-09-17 11:57 UTC by Lubomir Kundrak
Modified: 2019-09-29 12:21 UTC (History)
1 user (show)

Fixed In Version: 0.4.9-1.fc7
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2008-02-13 05:12:38 UTC

Attachments (Terms of Use)

Description Lubomir Kundrak 2007-09-17 11:57:57 UTC
Description of problem:

When duplicity's FTP backend calls ncftp, it passws the password argument via
command line. That's bad -- anyone can see that. On the other side, it's a very
good practice to overwrite the password string in the address space wfter it's
used, though it can still be viewed under a time-dependent race condition,
that's why I am cloning this to ncftp also.

Additional info:

See URL for the Deban BTS entry [1] for more details.
[1] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=442840

Comment 1 Lubomir Kundrak 2007-09-17 12:07:22 UTC
Bug #293091 is the ncftp one.

Comment 2 Lubomir Kundrak 2007-09-17 12:11:48 UTC
The CVE identifier for this was requested.

Comment 3 Robert Scheck 2007-09-17 12:13:59 UTC
Thanks for you report, Lubomir. Do you know, whether upstream was already 
notified about this security issue? I would like to avoid, that upstream and/or 
multiple downstreams are doing the same work in parallel.

Comment 4 Lubomir Kundrak 2007-09-17 15:17:03 UTC
Robert -- I have no idea whether upstream knows about the issue. I usually put
all information I know into the bug report. Please look at the debian bug to see
whether they did report and check the public mailing lists of the project (I
presume this would be reported via a public mailing list, as it's a public issue).

Also, please don't change the Version of the Product this report is assigned to.
I care about having this fixed in f7 and this report is also for my track. It is
usually natural that all fixes for problems from stable branches propagate to
devel, if devel is affected.

Comment 5 Robert Scheck 2007-09-17 15:33:50 UTC
I don't care about the version number, the issue has to be resolved in any
case for EL4, EL5, FC6 (when a fix comes up before EOL), F7 and F8/devel. I
will contact upstream directly to see, whether they know anything about it
this time.

Comment 6 Robert Scheck 2007-09-17 16:11:43 UTC
Here is the reply from the upstream guy:

Yes, I am aware of the problem.  One of the RCs used that solution. [comment: 
the FIFO I mentioned in my e-mail]

The problem is that the ncftp program has different command line and
control file semantics for at least three of the most recent versions of
the program.  Since we cannot lock the user into only one version of an
external program, I chose the path of least resistance.

Its an easy patch to make it work with a single version, but it would
break when ncftp is upgraded.  That's not a situation we want to get
into for any distro.


Disclaimer:  If you are on a system that is that insecure to begin with,
you need to rethink protocol.  Not only is it available on the command
line, but on the net.  Anyone with a sniffer could get it just as easy,
from inside and outside your net.

Comment 7 Lubomir Kundrak 2007-09-17 17:21:27 UTC
I'd say it's no problem to lock to a particular ncftp version we ship in Fedora,
and note a Require: on that version. It might be nice to put a comment above
Version: to both packages so that a developer that eventually bumps revision
ensures that he didn't break compatibility.

Comment 8 Robert Scheck 2007-09-17 18:02:28 UTC
I also don't see a problem to lock duplicity to a specific ncftp version, 
finally one more reply from upstream below:

I don't have a patch available.  That feature was in a version a few
iterations ago and used mkstemp() to securely make a temp file.  I'll
look into the FIFO option and get back to you.  It would be a good thing
to have a patch available for others to use if they wanted.

Comment 9 Robert Scheck 2007-09-19 09:03:41 UTC
Reply from upstream but only a possible solution for ncftp 3.2.1 which is not 
in all branches available IIRC:

Here's the fix for users of ncftp 3.2.1.  The previous versions of ncftp
have bugs relating to the use of -f, or require non-orthogonal command
options for the various utilities.



Comment 10 Robert Scheck 2007-09-19 12:11:47 UTC
More from upstream:


There have been a couple of upstream fixes that may be of interest:

Bug 21123 - duplicity does not find any backup chains - Important

Patch 6211 - restore strict host checking in sshBackend - Security


Comment 11 Lubomir Kundrak 2007-10-02 13:07:54 UTC
As you might get noticed, ncftp thingie was closed, and future versions of ncftp
will be overwriting the password in argv[] as it is used. Still a race though.

Robert: When would it be possible to roll an updated package?

Comment 12 Robert Scheck 2007-10-02 17:13:50 UTC
Ehm Lubomir, the ncftp bug report was marked as NOTABUG. Finally I can't see 
any fix which would work for all Fedora and EPEL branches...maybe you've to 
remove the tomatoes from my eyes, please?

Comment 13 Tomas Hoger 2007-10-05 06:43:56 UTC
CVE id CVE-2007-5201 was assigned to this issue.

Comment 14 Robert Scheck 2007-10-16 07:52:07 UTC
Lubomir? Ping? Can you please reply to comment #11? No reply, no update ;-)

Comment 15 Lubomir Kundrak 2007-11-01 22:28:22 UTC
Robert; Well, leave this open. Maybe once I'll find time to look at this. Mabye
you --- all in all, you're the maintainer and one that is responsible to keep
his package secure :)

Comment 17 Robert Scheck 2007-11-01 22:45:26 UTC
Please let me know, when a fix is available. Upstream doesn't see this as real 
issue and http://www.nongnu.org/duplicity/CHANGELOG doesn't point out changes 
regarding this.

Comment 18 Fedora Update System 2008-02-10 17:17:40 UTC
duplicity-0.4.9-1.fc7 has been submitted as an update for Fedora 7

Comment 19 Fedora Update System 2008-02-10 17:17:43 UTC
duplicity-0.4.9-1.fc8 has been submitted as an update for Fedora 8

Comment 20 Fedora Update System 2008-02-13 04:59:50 UTC
duplicity-0.4.9-1.fc8 has been pushed to the Fedora 8 stable repository.  If problems still persist, please make note of it in this bug report.

Comment 21 Fedora Update System 2008-02-13 05:12:23 UTC
duplicity-0.4.9-1.fc7 has been pushed to the Fedora 7 stable repository.  If problems still persist, please make note of it in this bug report.

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