lib/Crypto/PublicKey/ElGamal.py in PyCrypto through 2.6.1 generates weak ElGamal key parameters, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for PyCrypto’s ElGamal implementation.
github.com/advisories/GHSA-6528-wvf6-f6qg
github.com/dlitz/pycrypto
github.com/dlitz/pycrypto/issues/253
github.com/TElgamal/attack-on-pycrypto-elgamal
lists.debian.org/debian-lts-announce/2018/02/msg00018.html
nvd.nist.gov/vuln/detail/CVE-2018-6594
security.gentoo.org/glsa/202007-62
usn.ubuntu.com/3616-1
usn.ubuntu.com/3616-2