The sdump function in sdump.c in fetchmail 6.3.11, 6.3.12, and 6.3.13, when running in verbose mode on platforms for which char is signed, allows remote…

The sdump function in sdump.c in fetchmail 6.3.11, 6.3.12, and 6.3.13, when running in verbose mode on platforms for which char is signed, allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via an SSL X.509 certificate containing non-printable characters with the high bit set, which triggers a heap-based buffer overflow during escaping.