clamav -- heap overflow vulnerability

Clamav team reports:

A heap overflow vulnerability was discovered in libclamav
which could cause a denial of service or allow the
execution of arbitrary code.
The problem is specifically located in the PE file rebuild
function used by the UPX unpacker.
Relevant code from libclamav/upx.c:

    memcpy(dst, newbuf, foffset);
    *dsize = foffset;
    free(newbuf);

    cli_dbgmsg("UPX: PE structure rebuilt from compressed file\n");
    return 1;

Due to improper validation it is possible to overflow the above
memcpy() beyond the allocated memory block.