rsync 2.6.6pre1 released (ALERT: info on zlib security flaw)

Wayne Davison wayned at
Fri Jul 8 21:10:19 GMT 2005

[I neglected to cross-post this from the rsync-announce list to the
regular rsync mailing list when I sent this out yesterday.]

There has been some talk about a zlib security problem that could let
someone overflow the buffers in the zlib decompression code, potentially
allowing someone to craft an exploit to execute arbitrary code.  Since
this is a decompression bug, this can only affect an rsync daemon if
it allows uploads with the --compress option enabled.

If you run a daemon that allows uploads, you may wish to add this line
to your rsyncd.conf file:

    refuse options = compress

(If you already refuse other options, add "compress" after a space to
that line instead of adding a new line.)

I have just finished updating the zlib code in CVS to version 1.2.2 plus
a security patch that fixes this latest exploit.  The other changes in
CVS are all worthwhile fixes, so I have decided to release the current
CVS version as 2.6.6pre1 -- the first pre-release of version 2.6.6.

You can read about all the changes between 2.6.5 and 2.6.6pre1 here:

You can grab the source tar and its signature here:

If you exercise the compression code of this pre-release version of
rsync, please drop me a line and let me know.  Thanks!


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