Description
When running Apache Tomcat versions 9.0.0.M1 to 9.0.0, 8.5.0 to 8.5.22, 8.0.0.RC1 to 8.0.46 and 7.0.0 to 7.0.81 with HTTP PUTs enabled (e.g. via setting the readonly initialisation parameter of the Default servlet to false) it was possible to upload a JSP file to the server via a specially crafted request. This JSP could then be requested and any code it contained would be executed by the server.
Remediation
References
http://www.securityfocus.com/bid/100954
https://www.exploit-db.com/exploits/42966/
http://www.securitytracker.com/id/1039552
https://www.exploit-db.com/exploits/43008/
https://security.netapp.com/advisory/ntap-20171018-0002/
https://access.redhat.com/errata/RHSA-2017:3114
https://access.redhat.com/errata/RHSA-2017:3113
https://access.redhat.com/errata/RHSA-2017:3081
https://access.redhat.com/errata/RHSA-2017:3080
https://security.netapp.com/advisory/ntap-20180117-0002/
http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
https://access.redhat.com/errata/RHSA-2018:0275
https://access.redhat.com/errata/RHSA-2018:0271
https://access.redhat.com/errata/RHSA-2018:0270
https://access.redhat.com/errata/RHSA-2018:0269
https://access.redhat.com/errata/RHSA-2018:0268
https://access.redhat.com/errata/RHSA-2018:0466
https://access.redhat.com/errata/RHSA-2018:0465
http://www.oracle.com/technetwork/security-advisory/cpuapr2018-3678067.html
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03828en_us
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03812en_us
https://usn.ubuntu.com/3665-1/
http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
https://access.redhat.com/errata/RHSA-2018:2939
https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html
https://support.f5.com/csp/article/K53173544
https://lists.debian.org/debian-lts-announce/2017/11/msg00009.html
https://lists.apache.org/thread.html/3fd341a604c4e9eab39e7eaabbbac39c30101a022acc11dd09d7ebcb%40%3Cannounce.tomcat.apache.org%3E
https://lists.apache.org/thread.html/eb6efa8d59c45a7a9eff94c4b925467d3b3fec8ba7697f3daa314b04%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/343558d982879bf88ec20dbf707f8c11255f8e219e81d45c4f8d0551%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/388a323769f1dff84c9ec905455aa73fbcb20338e3c7eb131457f708%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/5c0e00fd31efc11e147bf99d0f03c00a734447d3b131ab0818644cdb%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/b5e3f51d28cd5d9b1809f56594f2cf63dcd6a90429e16ea9f83bbedc%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/88855876c33f2f9c532ffb75bfee570ccf0b17ffa77493745af9a17a%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/e85e83e9954f169bbb77b44baae5a33d8de878df557bb32b7f793661%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/845312a10aabbe2c499fca94003881d2c79fc993d85f34c1f5c77424%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/1dd0a59c1295cc08ce4c9e7edae5ad2268acc9ba55adcefa0532e5ba%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/3d19773b4cf0377db62d1e9328bf9160bf1819f04f988315086931d7%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/6af47120905aa7d8fe12f42e8ff2284fb338ba141d3b77b8c7cb61b3%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r6ccee4e849bc77df0840c7f853f6bd09d426f6741247da2b7429d5d9%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r3bbb800a816d0a51eccc5a228c58736960a9fffafa581a225834d97d%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r9136ff5b13e4f1941360b5a309efee2c114a14855578c3a2cbe5d19c%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/raba0fabaf4d56d4325ab2aca8814f0b30a237ab83d8106b115ee279a%40%3Cdev.tomcat.apache.org%3E
https://lists.apache.org/thread.html/r48c1444845fe15a823e1374674bfc297d5008a5453788099ea14caf0%40%3Cdev.tomcat.apache.org%3E
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