The problem can be corrected by upgrading the affected package to
version 4.0.4-28ubuntu2.1 (for Ubuntu 4.10), 4.0.4-29ubuntu1.1 (for
Ubuntu 5.04), or 4.0.4-31ubuntu1.1 (for Ubuntu 5.10). In general, a
standard system upgrade is sufficient to effect the necessary changes.
USN-148-1 and USN-151-1 fixed two security flaws in zlib, which could
be exploited to cause Denial of Service attacks or even arbitrary code
execution with malicious data streams.
Since lsb-rpm is statically linked against the zlib library, it is also
affected by these issues. The updated packagages have been rebuilt
against the fixed zlib.
Please note that lsb-rpm is not officially supported (it is in the "universe"
component of the archive).