dnf crashes make fedpkg / mock unusable

Hi everybody, Since about one or two days, I am completely unable to build any packages with fedpkg locally, and even running dnf on the host system is really crashy. It looks like dnf crashes while it's refreshing repository metadata. ABRT won't let me report the issue due to "low informational value" of the backtrace, but it looks like SEGFAULT in libcurl: Program terminated with signal SIGSEGV, Segmentation fault. #0 0x00007fad55077f22 in ?? () from /lib64/libcurl.so.4 (...) However, there's not been any recent curl update for f29 AFAICT. I tried cleaning up the dnf cache, but it doesn't help. Does anybody have an idea what's causing this? I'm unable to work on my packages until I can solve this .... Fabio