Compiling openssl 1.0.2 (cygwin)

Your app is running an outdated version of OpenSSL, which has multiple security vulnerabilities. You should update OpenSSL as soon as possible.

The following seems to work
Download openssl-1.0.2g.tar.gz from site: https://www.openssl.org/source/
untar to some directory (openssl-1.0.2g) is the default
ex: tar -xf openssl-1.0.2g.tar.gz

runup cygwin

cd to openssl-1.0.2g – then issue the following command
./config
make depend
make install
– you are done
ls *.a
libcrypto.a libssl.a

just replace these files in .\external\curl\prebuilt

Good luck
Andre