What’s Vulnerable › Vulnerabilities

CVE-2018-6594

• Severity: high (CVSS 7.5 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.0% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2018-02-03 · updated 2026-06-17
• Weakness: CWE-326

Description

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.

Affected products

• Canonical Ubuntu Linux: 12.04, 14.04, 16.04, 17.10
• Debian Linux: 7.0
• Dlitz Pycrypto: through 2.6.1

References

• https://github.com/TElgamal/attack-on-pycrypto-elgamal
• https://github.com/dlitz/pycrypto/issues/253
• https://lists.debian.org/debian-lts-announce/2018/02/msg00018.html
• https://security.gentoo.org/glsa/202007-62
• https://usn.ubuntu.com/3616-1/
• https://usn.ubuntu.com/3616-2/
• https://github.com/TElgamal/attack-on-pycrypto-elgamal
• https://github.com/dlitz/pycrypto/issues/253
• https://lists.debian.org/debian-lts-announce/2018/02/msg00018.html
• https://security.gentoo.org/glsa/202007-62
• https://usn.ubuntu.com/3616-1/
• https://usn.ubuntu.com/3616-2/

Get alerted when CVE-2018-6594 or the next vulnerability affects your stack