{"id":"UBUNTU-CVE-2018-6594","details":"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.","modified":"2026-02-04T03:51:06.182704Z","published":"2018-02-03T00:00:00Z","related":["USN-3616-1","USN-3616-2"],"upstream":["CVE-2018-6594"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2018-6594"},{"type":"REPORT","url":"https://github.com/TElgamal/attack-on-pycrypto-elgamal"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3616-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-3616-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2018-6594"}],"affected":[{"package":{"name":"python-crypto","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/python-crypto@2.6.1-4ubuntu0.3?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.6.1-4ubuntu0.3"}]}],"versions":["2.6-5","2.6.1-2","2.6.1-2build1","2.6.1-3","2.6.1-4","2.6.1-4build1","2.6.1-4ubuntu0.1","2.6.1-4ubuntu0.2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"python-crypto","binary_version":"2.6.1-4ubuntu0.3"},{"binary_name":"python3-crypto","binary_version":"2.6.1-4ubuntu0.3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-6594.json"}},{"package":{"name":"python-crypto","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/python-crypto@2.6.1-6ubuntu0.16.04.3?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.6.1-6ubuntu0.16.04.3"}]}],"versions":["2.6.1-5build1","2.6.1-6","2.6.1-6build1","2.6.1-6ubuntu0.16.04.1","2.6.1-6ubuntu0.16.04.2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_version":"2.6.1-6ubuntu0.16.04.3","binary_name":"python-crypto"},{"binary_version":"2.6.1-6ubuntu0.16.04.3","binary_name":"python3-crypto"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-6594.json"}},{"package":{"name":"pycryptodome","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/pycryptodome@3.4.7-1ubuntu1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.7-1ubuntu1"}]}],"versions":["3.4.6-1","3.4.7-1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"python-pycryptodome","binary_version":"3.4.7-1ubuntu1"},{"binary_version":"3.4.7-1ubuntu1","binary_name":"python3-pycryptodome"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-6594.json"}},{"package":{"name":"python-crypto","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/python-crypto@2.6.1-8ubuntu2?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.6.1-8ubuntu2"}]}],"versions":["2.6.1-7build2","2.6.1-8"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"python-crypto","binary_version":"2.6.1-8ubuntu2"},{"binary_name":"python3-crypto","binary_version":"2.6.1-8ubuntu2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2018/UBUNTU-CVE-2018-6594.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]}