콘솔창에 뜨는 메세지 질문입니다;;

안녕하세요.

며칠 전부터 콘솔창에서 이런 메세지가 뜨는데, 무슨 말인지 검색해보아도

잘 안나오고, 도통 알수가 없어, superuser 분들에 도움을 구하고자 합니다.

제발 답변 부탁드립니다. ;;;;;;;;;;;;;;;;

-------------------메세지 내용------------------------------------

Dec  7 07:38:51 adam sendmail[2642]: [ID 801593 mail.alert] kB6Mclsf002641: Fixed MIME Content-ID header (possible attack)
Dec  7 07:57:17 adam sendmail[2803]: [ID 801593 mail.alert] kB6MvEsf002801: Fixed MIME Content-ID header (possible attack)
Dec  7 08:18:13 adam sendmail[3303]: [ID 801593 mail.alert] kB6NI8sf003299: Fixed MIME Content-ID header (possible attack)
Dec  7 08:21:46 adam sendmail[3364]: [ID 801593 mail.alert] kB6NLcsf003358: Fixed MIME Content-ID header (possible attack)
Dec  7 08:53:51 adam sendmail[3979]: [ID 801593 mail.alert] kB6Nrmsf003976: Fixed MIME Content-ID header (possible attack)
Dec  7 09:26:14 adam sendmail[4854]: [ID 801593 mail.alert] kB70Q7sf004846: Fixed MIME Content-ID header (possible attack)
Dec  7 09:30:29 adam sendmail[4986]: [ID 801593 mail.alert] kB70UEsf004968: Fixed MIME Content-ID header (possible attack)
Dec  7 09:51:12 adam sendmail[5785]: [ID 801593 mail.alert] kB70p9sf005783: Fixed MIME Content-ID header (possible attack)
Dec  7 09:51:33 adam sendmail[5804]: [ID 801593 mail.alert] kB70pVsf005801: Fixed MIME Content-ID header (possible attack)
Dec  7 09:51:32 adam last message repeated 8 times
Dec  7 09:51:33 adam sendmail[5785]: [ID 801593 mail.alert] kB70p9sf005783: Fixed MIME Content-ID header (possible attack)
Dec  7 09:52:03 adam last message repeated 16 times
Dec  7 09:56:10 adam sendmail[5995]: [ID 801593 mail.alert] kB70u8sf005992: Fixed MIME Content-ID header (possible attack)
Dec  7 10:39:35 adam sendmail[6965]: [ID 801593 mail.alert] kB71dWsf006963: Fixed MIME Content-ID header (possible attack)
Dec  7 12:02:49 adam sendmail[8233]: [ID 801593 mail.alert] kB732lsf008229: Fixed MIME Content-ID header (possible attack)
Dec  7 12:32:06 adam sendmail[6200]: [ID 801593 mail.alert] kB70p9sf005783: Fixed MIME Content-ID header (possible attack)
Dec  7 12:32:12 adam last message repeated 2 times
Dec  7 14:20:21 adam sendmail[12812]: [ID 801593 mail.alert] kB75KIsf012809: Fixed MIME Content-ID header (possible attack)
Dec  7 14:20:22 adam last message repeated 1 time
Dec  7 14:24:23 adam sendmail[12893]: [ID 801593 mail.alert] kB75OLsf012889: Fixed MIME Content-ID header (possible attack)
Dec  7 14:25:05 adam sendmail[12914]: [ID 801593 mail.alert] kB75Oxsf012909: Fixed MIME Content-ID header (possible attack)
Dec  7 14:29:08 adam sendmail[12987]: [ID 801593 mail.alert] kB75Susf012979: Fixed MIME Content-ID header (possible attack)
Dec  7 14:44:45 adam sendmail[13454]: [ID 801593 mail.alert] kB75iYsf013436: Fixed MIME Content-ID header (possible attack)
Dec  7 14:45:30 adam sendmail[13467]: [ID 801593 mail.alert] kB75jDsf013464: Fixed MIME Content-ID header (possible attack)
Dec  7 14:45:30 adam last message repeated 1 time
Dec  7 14:56:33 adam sendmail[13727]: [ID 801593 mail.alert] kB75uVsf013726: Fixed MIME Content-ID header (possible attack)
Dec  7 15:13:41 adam sendmail[7205]: [ID 801593 mail.alert] kB70p9sf005783: Fixed MIME Content-ID header (possible attack)
Dec  7 15:31:07 adam sendmail[14539]: [ID 801593 mail.alert] kB76V4sf014536: Fixed MIME Content-ID header (possible attack)
Dec  7 16:16:57 adam sendmail[16077]: [ID 801593 mail.alert] kB77Glsf016064: Fixed MIME Content-ID header (possible attack)