InfoSect's Month of Pointless Bugs (#28)

Dr Silvio Cesare

InfoSect, Canberra's hackerspace, regularly runs public group sessions to perform code review and vulnerability discovery. Over the next 30 days, I'll highlight the source code of 30 unknown vulnerabilities.

Bug #28

The canfield game in bsdgames doesn't check if dropping privs can fail - see http://blog.infosectcbr.com.au/2018/02/infosects-month-of-pointless-bugs-3.html


bsdgames/canfield/canfield/canfield.c

        if (uid < 0)
                uid = 0;
        dbfd = open(_PATH_SCORE, O_RDWR);

         /* Revoke setgid privileges */
        setregid(getgid(), getgid());

         if (dbfd < 0)
                return;

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