libtasn1 version 2.12 was released fixing the following issue:

- Corrected DER decoding issue (reported by Matthew Hall). Added self check to detect the problem, see tests/Testoverflow.c. This problem can lead to at least remotely triggered crashes, see further analysis on the libtasn1 mailing list.

http://thread.gmane.org/gmane.comp.gnu.libtasn1.general/53

Upstream and few limited details are available at:

http://thread.gmane.org/gmane.comp.gnu.libtasn1.general/54

The behavior of asn1getlengthder was changed to protect against accidental incorrect use, if though it was previously "working properly and as documented".