| Name | CVE-2018-6594 |
| 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. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 889998, 889999 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| pycryptodome (PTS) | bullseye | 3.9.7+dfsg1-1 | fixed |
| bookworm | 3.11.0+dfsg1-4 | fixed |
| sid, trixie | 3.20.0+dfsg-3 | fixed |
The information below is based on the following data on fixed versions.
Notes
[stretch] - python-crypto <no-dsa> (Minor issue)
[jessie] - python-crypto <no-dsa> (Minor issue)
[wheezy] - python-crypto <no-dsa> (Minor issue)
PyCrypto: https://github.com/dlitz/pycrypto/issues/253
The issue is found as well in pycryptodome (fork from python-crypto)
PyCryptodome: https://github.com/Legrandin/pycryptodome/issues/90
PyCrytpodome: https://github.com/Legrandin/pycryptodome/commit/99c27a3b9e8a884bbde0e88c63234b669d4398d8 (3.4.10)
See further discussion as per https://github.com/Legrandin/pycryptodome/issues/90#issuecomment-362783537
Upstream feels that this is not a vulnerability in pycryptodome/python-crypto,
but in an application using it in an insecure manner.