pdf.c in ClamAV 0.97.1 through 0.97.7 allows remote attackers to cause a denial of service (out-of-bounds-read) via a crafted length value in an encrypted PDF file. Per http://www.ubuntu.com/usn/USN-1816-1/
"A security issue affects these releases of Ubuntu and its derivatives:
Ubuntu 13.04
Ubuntu 12.10
Ubuntu 12.04 LTS
Ubuntu 11.10
Ubuntu 10.04 LTS"
Publication date: Mon, 28 Sep 2015 21:33:00 +0000