[Full-Disclosure] Re: FluxBox crash vulnerability

From: Tim (tim-security_at_sentinelchicken.org)
Date: 11/27/04

  • Next message: Daniel H. Renner: "[Full-Disclosure] "<01><02>_msbro"?"
    To: Quith <quith@linux-hell.net>
    Date: Fri, 26 Nov 2004 20:31:31 -0500

    > Fluxbox always crashes totally while executing XMAN with long value of
    > '-title' parameter. Simple usage example:
    > $ xman -title `perl -e 'print "X" x 10000 '`
    > It was tested on 0.9.10 version and some older ones. Probably all are affected.

    Please see tests below:

    ~> fluxbox -version
    Fluxbox 0.9.9 : (c) 2001-2004 Henrik Kinnunen
    ~> uname -o -r
    2.6.8 GNU/Linux
    ~> cat /etc/debian_version
    ~> xman -title `perl -e 'print "X" x 8936 '`
    X connection to :0.0 broken (explicit kill or server shutdown).

    So, the gist of it is, on the version I am running I could never get
    fluxbox to crash. However, large titles did cause problems. with
    anything above, say, 5000 characters, the window comes up, but is very
    unresponsive. Resizing the window causes display refresh problems for
    that window, and the whole window manager is generally slow.

    However, as soon as I close the window, everything returns to normal.
    In addition, using any number of characters above 8936 does not cause
    this behavior at all, because for 8937 and above, the title bar displays
    nothing and everything is peachy. Large titles just under that amount
    cause issues, and it appears the X's in the title wrap around an
    overwrite themselves in the display. When there were problems with the
    window, sometimes (maybe 1 in 4) I get the error message you see above.

    I get these same symptoms when using large titles on other programs as


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  • Next message: Daniel H. Renner: "[Full-Disclosure] "<01><02>_msbro"?"