icu - multiple problems

Several local vulnerabilities have been discovered in libicu,
International Components for Unicode, The Common Vulnerabilities and
Exposures project identifies the following problems:

• CVE-2007-4770

libicu in International Components for Unicode (ICU) 3.8.1 and earlier
attempts to process backreferences to the nonexistent capture group
zero (aka \0), which might allow context-dependent attackers to read
from, or write to, out-of-bounds memory locations, related to
corruption of REStackFrames.

• CVE-2007-4771

Heap-based buffer overflow in the doInterval function in regexcmp.cpp
in libicu in International Components for Unicode (ICU) 3.8.1 and
earlier allows context-dependent attackers to cause a denial of
service (memory consumption) and possibly have unspecified other
impact via a regular expression that writes a large amount of data to
the backtracking stack.

For the stable distribution (etch), these problems have been fixed in
version 3.6-2etch1.

For the unstable distribution (sid), these problems have been fixed in
version 3.8-6.

We recommend that you upgrade your libicu package.