数据库 外文翻译 外文文献 英文文献 数据库安全

DATABASESECURITY“WHYDOINEEDTOSECUREMYDATABASESERVERNOONECANACCESSITITSINADMZPROTECTEDBYTHEFIREWALL”THISISOFTENTHERESPONSEWHENITISRECOMMENDEDTHATSUCHDEVICESAREINCLUDEDWITHINASECURITYHEALTHCHECKINFACT,DATABASESECURITYISPARAMOUNTINDEFENDINGANORGANIZATIONSINFORMATION,ASITMAYBEINDIRECTLYEXPOSEDTOAWIDERAUDIENCETHANREALIZEDTHISISTHEFIRSTOFTWOARTICLESTHATWILLEXAMINEDATABASESECURITYINTHISARTICLEWEWILLDISCUSSGENERALDATABASESECURITYCONCEPTSANDCOMMONPROBLEMSINTHENEXTARTICLEWEWILLFOCUSONSPECIFICMICROSOFTSQLANDORACLESECURITYCONCERNSDATABASESECURITYHASBECOMEAHOTTOPICINRECENTTIMESWITHMOREANDMOREPEOPLEBECOMINGINCREASINGLYCONCERNEDWITHCOMPUTERSECURITY,WEAREFINDINGTHATFIREWALLSANDWEBSERVERSAREBEINGSECUREDMORETHANEVERTHOUGHTHISDOESNOTMEANTHATTHEREARENOTSTILLALARGENUMBEROFINSECURENETWORKSOUTTHEREASSUCH,THEFOCUSISEXPANDINGTOCONSIDERTECHNOLOGIESSUCHASDATABASESWITHAMORECRITICALEYECOMMONSENSESECURITYBEFOREWEDISCUSSTHEISSUESRELATINGTODATABASESECURITYITISPRUDENTTOHIGHLIGHTTHENECESSITYTOSECURETHEUNDERLYINGOPERATINGSYSTEMANDSUPPORTINGTECHNOLOGIESITISNOTWORTHSPENDINGALOTOFEFFORTSECURINGADATABASEIFAVANILLAOPERATINGSYSTEMISFAILINGTOPROVIDEASECUREBASISFORTHEHARDENINGOFTHEDATABASETHEREAREALARGENUMBEROFEXCELLENTDOCUMENTSINTHEPUBLICDOMAINDETAILINGMEASURESTHATSHOULDBEEMPLOYEDWHENINSTALLINGVARIOUSOPERATINGSYSTEMSONECOMMONPROBLEMTHATISOFTENENCOUNTEREDISTHEEXISTENCEOFADATABASEONTHESAMESERVERASAWEBSERVERHOSTINGANINTERNETORINTRANETFACINGAPPLICATIONWHILSTTHISMAYSAVETHECOSTOFPURCHASINGASEPARATESERVER,ITDOESSERIOUSLYAFFECTTHESECURITYOFTHESOLUTIONWHERETHISISIDENTIFIED,ITISOFTENTHECASETHATTHEDATABASEISOPENLYCONNECTEDTOTHEINTERNETONERECENTEXAMPLEICANRECALLISANAPACHEWEBSERVERSERVINGANORGANIZATIONSINTERNETOFFERING,WITHANORACLEDATABASEAVAILABLEONTHEINTERNETONPORT1521WHENINVESTIGATINGTHISISSUEFURTHERITWASDISCOVEREDTHATACCESSTOTHEORACLESERVERWASNOTPROTECTEDINCLUDINGLACKOFPASSWORDS,WHICHALLOWEDTHESERVERTOBESTOPPEDTHEDATABASEWASNOTREQUIREDFROMANINTERNETFACINGPERSPECTIVE,BUTTHEUSEOFDEFAULTSETTINGSANDCARELESSSECURITYMEASURESRENDEREDTHESERVERVULNERABLETHEPOINTSMENTIONEDABOVEARENOTSTRICTLYDATABASEISSUES,ANDCOULDBECLASSIFIEDASARCHITECTURALANDFIREWALLPROTECTIONISSUESALSO,BUTULTIMATELYITISTHEDATABASETHATISCOMPROMISEDSECURITYCONSIDERATIONSHAVETOBEMADEFROMALLPARTSOFAPUBLICFACINGNETWORKYOUCANNOTRELYONSOMEONEORSOMETHINGELSEWITHINYOURORGANIZATIONPROTECTINGYOURDATABASEFROMEXPOSUREATTACKTOOLSARENOWAVAILABLEFOREXPLOITINGWEAKNESSESINSQLANDORACLEICAMEACROSSONEINTERESTINGASPECTOFDATABASESECURITYRECENTLYWHILECARRYINGOUTASECURITYREVIEWFORACLIENTWEWEREPERFORMINGATESTAGAINSTANINTRANETAPPLICATION,WHICHUSEDADATABASEBACKENDSQLTOSTORECLIENTDETAILSTHESECURITYREVIEWWASPROCEEDINGWELL,WITHACCESSCONTROLSBEINGBASEDONWINDOWSAUTHENTICATIONONLYAUTHENTICATEDWINDOWSUSERSWEREABLETOSEEDATABELONGINGTOTHEMTHEAPPLICATIONITSELFSEEMEDTOBEHANDLINGINPUTREQUESTS,REJECTINGALLATTEMPTSTOACCESSTHEDATABASEDIRECTLYWETHENHAPPENEDTOCOMEACROSSABACKUPOFTHEAPPLICATIONINTHEOFFICEINWHICHWEWEREWORKINGTHISMEDIACONTAINEDABACKUPOFTHESQLDATABASE,WHICHWERESTOREDONTOOURLAPTOPALLSECURITYCONTROLSWHICHWEREINPLACEORIGINALLYWERENOTRESTOREDWITHTHEDATABASEANDWEWEREABLETOBROWSETHECOMPLETEDATABASE,WITHNORESTRICTIONSINPLACETOPROTECTTHESENSITIVEDATATHISMAYSEEMLIKEACONTRIVEDWAYOFCOMPROMISINGTHESECURITYOFTHESYSTEM,BUTDOESHIGHLIGHTANIMPORTANTPOINTITISOFTENNOTTHEDIRECTAPPROACHTHATISTAKENTOATTACKATARGET,ANDULTIMATELYTHEENDPOINTISTHESAMESYSTEMCOMPROMISEABACKUPCOPYOFTHEDATABASEMAYBESTOREDONTHESERVER,ANDTHUSFACILITATESACCESSTOTHEDATAINDIRECTLYTHEREISASIMPLESOLUTIONTOTHEPROBLEMIDENTIFIEDABOVESQL2000CANBECONFIGUREDTOUSEPASSWORDPROTECTIONFORBACKUPSIFTHEBACKUPISCREATEDWITHPASSWORDPROTECTION,THISPASSWORDMUSTBEUSEDWHENRESTORINGTHEPASSWORDTHISISANEFFECTIVEANDUNCOMPLICATEDMETHODOFSTOPPINGSIMPLECAPTUREOFBACKUPDATAITDOESHOWEVERMEANTHATTHEPASSWORDMUSTBEREMEMBEREDCURRENTTRENDSTHEREAREANUMBEROFCURRENTTRENDSINITSECURITY,WITHANUMBEROFTHESEBEINGLINKEDTODATABASESECURITYTHEFOCUSONDATABASESECURITYISNOWATTRACTINGTHEATTENTIONOFTHEATTACKERSATTACKTOOLSARENOWAVAILABLEFOREXPLOITINGWEAKNESSESINSQLANDORACLETHEEMERGENCEOFTHESETOOLSHASRAISEDTHESTAKESANDWEHAVESEENFOCUSEDATTACKSAGAINSTSPECIFICDATABASEPORTSONSERVERSEXPOSEDTOTHEINTERNETONECOMMONTHEMERUNNINGTHROUGHTHESECURITYINDUSTRYISTHEFOCUSONAPPLICATIONSECURITY,ANDINPARTICULARBESPOKEWEBAPPLICATIONSWITHHEFUNCTIONALITYOFWEBAPPLICATIONSBECOMINGMOREANDMORECOMPLEX,ITBRINGSTHEPOTENTIALFORMORESECURITYWEAKNESSESINBESPOKEAPPLICATIONCODEINORDERTOFULFILLTHEFUNCTIONALITYOFAPPLICATIONS,THEBACKENDDATASTORESARECOMMONLYBEINGUSEDTOFORMATTHECONTENTOFWEBPAGESTHISREQUIRESMORECOMPLEXCODINGATTHEAPPLICATIONENDWITHDEVELOPERSUSINGDIFFERENTSTYLESINCODEDEVELOPMENT,SOMEOFWHICHARENOTASSECURITYCONSCIOUSASOTHER,THISCANBETHESOURCEOFEXPLOITABLEERRORSSQLINJECTIONISONESUCHHOTTOPICWITHINTHEITSECURITYINDUSTRYATTHEMOMENTDISCUSSIONSARENOWCOMMONPLACEAMONGTECHNICALSECURITYFORUMS,WITHMOREANDMOREWAYSANDMEANSOFEXPLOITINGDATABASESCOMINGTOLIGHTALLTHETIMESQLINJECTIONISAMISLEADINGTERM,ASTHECONCEPTAPPLIESTOOTHERDATABASES,INCLUDINGORACLE,DB2ANDSYBASEWHATISSQLINJECTIONSQLINJE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的空间。我在最近为客户做的一项安全评估中偶然发现一个数据库安全方面的有趣的是。我们正在进行对使用一个数据库后端（SQL）以存放客户端的细节的企业内部应用软件的测试。安全审查过程进展顺利，访问控制基于WINDOWS认证。只有通过认证的WINDOWS用户能够看到属于他们的数据。这个应用软件本身好像对输入要求进行处理，拒绝直接进入资料库的所有尝试。之后我们在工作的办公室偶然发现一个该应用软件的备份。这个媒体装有SQL数据库的备份，这是我们重新存储到笔记本电脑上的。所有安全控制均到那些原先并未恢复数据库的位置上，而且我们能够在适当的位置无任何限制地浏览完整的数据库，以保护敏感的数据。这可能像是一种妥协的系统安全的方式，但确实是重要的。往往并不是采取直接的方法攻击一个目标，并且最终结果是相同的系统妥协。数据库备份可以存储在服务器上，从而有利于间接地访问数据。以上问题有一个简单的办法来解决。在SQL2000可以为备份设定使用密码保护。如果备份使用了密码保护，当创建密码时就必须使用密码。这是一种有效而且不太复杂的方法阻止备份数据的简单捕获。然而这意味着密码必须记住当前趋势在IT安全方面有许多当前趋势，这些中的不少都与数据库安全联系起来。数据库安全方面的焦点正吸引着攻击者的注意力。由于SQL和ORACLE开发的漏洞给攻击工具一个得以使用的空间。这些工具的出现提高了赌注，我们已经看到，攻击主要是针对服务器暴露到互联网的特定数据库端口。贯穿安全业的一个普遍问题是应用软件安全，特别是定制的WEB应用程序。随着WEB应用程序的功能变得越来越复杂，它带来了应用程序编码方面的安全漏洞的更大的潜在威胁。为了满足应用软件的功能性要求，后端数据存储通常被用来安排网页内容的格式。这就需要更复杂的后端数据编码。开发者使用不同风格的代码开发，其中一部分没有安全意识，这也许是开发错误的源头。SQL注入就是当前IT安全业的一个热门话题。随着愈来愈多的以期缩短时间的开发数据库的方式和手段的出现，目前在技术安全论坛中，争论是很平常的。SQL注入是一个容易让人误导的术语，因为该概念也适用于其他的数据库，包括ORACLE，DB2和SYBASE系统。什么是SQL注入SQL注入的是软件开发人员所不希望出现的与资料库使用代码或指令发送手段的交流方法。这是发现在WEB应用软件最常见的形式。任何用户输入应用软件所不允许的内容是攻击的一个常见来源。在座很多朋友已经看到了当访问网站时通常的错误消息框，而且往往显示用户输入没有得到正确处理。一旦出现这种类型的错误，攻击者将把焦点放在更具体的输入字符串上。具体的与安全有关的编码技术在使用组织时应加入编码标准。由于这种类型的脆弱性所造成的损害，可以很深刻的，尽管这会取决于该应用软件与数据库关联的特权级别。如果该软件以管理者类型权限访问数据，然后恶意运行命令也会是这一级别的访问权限，此时系统妥协是不可避免的。还有这个问题类似于操作系统的安全规则，在那里，项目应该以最低的权限运行，而且这是必要的。如果是正常的用户访问，然后启用