GnuPG 2.0.22 is a security fix release and all users are advised to updated to this version.
- Fixed possible infinite recursion in the compressed packet parser. [CVE-2013-4402]
- Improved support for some card readers.
- Prepared building with the forthcoming Libgcrypt 1.6.
- Protect against rogue keyservers sending secret keys.
Impact of the security problem
Special crafted input data may be used to cause a denial of service against GPG (GnuPG’s OpenPGP part) and some other OpenPGP implementations. All systems using GPG to process incoming data are affected.
Taylor R. Campbell invented a neat trick to generate OpenPGP packages to force GPG to recursively parse certain parts of OpenPGP messages ad infinitum. As a workaround a tight “ulimit -v” setting may be used to mitigate the problem. Sample input data to trigger this problem has not yet been seen in the wild. Details of the attack will eventually be published by its inventor.
A fixed release of the GnuPG 1.4 series has also been released.
An updated vesion of gpg4win will be released next week.