Package: gpg Version: gnupg Severity: normal Tags: security Hello,
The default cipher in gpg and gpg2 for symmetric encryption is CAST-5. CAST-5 block size is 64 bits and the cipher is used in CFB mode. CFB mode in vulnerable to a practical attack when the size of the ciphertext is close to sqrt(block_size). In the case of CAST-5 as well as for Blowfish and 3DES it happens when the message more than ~ 1 Go long. The problem has been solved upstream and in sid but not in jessie. The following commits are available in the Git repository of GnuPG: * fc30a414d8d6586207444356ec270bd3fe0f6e68 for gpg; * 57df1121c18b004dd763b35eabf7b51fc9e8ec38 for gpg2. Have a nice day. Piotr Chmielnicki -- System Information: Debian Release: 8.4 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system)
