CVE-2015-5287: Medium severity red hat automatic bug reporting tool vulnerability

A vulnerability allowing to elevate privileges from the abrt user to root was reported. If a program starting with the name "abrt" crashes, abrt-hook-ccpp will write the coredump to /var/tmp/abrt/$filename-coredump or /var/spool/abrt/$filename-coredump. From abrt-hook-ccpp.c:

if (lastslash && strncmp(++lastslash, "abrt", 4) == 0) { / If abrtd/abrt-foo crashes, we don't want to create a directory, since that can make new copy of abrtd to process it, and maybe crash again... Unlike dirs, mere files are ignored by abrtd. / if (snprintf(path, sizeof(path), "%s/%s-coredump", gsettingsdumplocation, lastslash) >= sizeof(path)) errormsganddie("Error saving '%s': truncated long file path", path);

int abrtcorefd = xopen3(path, OWRONLY | OCREAT | OTRUNC, 0600);

The call to xopen3() does not include the flag ONOFOLLOW and is therefore vulnerable to a symlink attack.

This vulnerability is not exploitable on RHEL installations with default configuration. It can be exploitable if the system is configured to use non-RHN yum repositories. This is because yum is normally not usable by non-root users if the only configured repositories are RHN.

Note: This security flaw has been split from bug #1262252.