You should rebuild using libgmp >= 5 to avoid timing attack vulnerability

getting this on your linux when trying to run something?

You should rebuild using libgmp >= 5 to avoid timing attack vulnerability. _warn("Not using mpz_powm_sec. You should rebuild using libgmp >= 5 to avoid timing attack vulnerability.", PowmInsecureWarning)

yup, seen it…

RHEL has GMP version 4.something
PyCrypto needs GMP >= 5

RHEL is a tad behind we have to re-make The GNU Multiple Precision Arithmetic Library stuff.

solution:

1. download the sources from https://gmplib.org/#DOWNLOAD

2. and according to the instructions from the package:

   tar -xvjpf gmp-6.0.0a.tar.bz2
   ./configure 
   make 
   make check
   make install 
   
   

3. rebuild PyCrypto

   pip install --ignore-installed PyCrypto

4. for good measure, re-build and re-install some stuff (trust me, just go with it)

   yum -y groupinstall "Development tools" 
   yum -y install gcc libgcc glibc libffi-devel libxml2-devel libxslt-devel openssl-devel zlib-devel bzip2-devel ncurses-devel

tada! send me a nice thank you note when you’re done.