Hey Alex, I can reproduce the following: rm -f bla touch bla screen -L bla -> file bla still owned by myself and filled in with log file contents.
rm -f bla screen -L bla -> file bla created with owner root and filled in with log file contents. sudo rm -f bla echo hello world | sudo dd od=bla screen -L bla -> file bla still owned by root but truncated to length 0. Reverting the initial write check http://git.savannah.gnu.org/cgit/screen.git/commit/?h=screen-v4&id=5460f5d28c01a9a58e021eb1dffef2965e629d58 should fix it. Please test. Please let me know as soon as I can test. cheers, JW- PS: when I first saw the code I wondered what the use case was and immediatly thought of an exploit. But with the initial test and everything I was conviced it should be good. Damed... On Tue, Jan 24, 2017 at 11:23 PM, Alex Naumov <alexander_nau...@opensuse.org> wrote: > Hi Axel, > > I also can't reproduce it, but it's depend on how do you install > GNU screen and which security mechanisms do you use in your OS. > > There is 2 very nasty bugs and one of them is security related... > > As I said, I'm working on that and going to release 4.5.1 as a > security/bugfix release next month. >
