Vulnerable Apache Solr, Redis, Windows servers hit with cryptominers

Remote code execution occurs in Apache Solr before 7.1 with Apache Lucene before 7.1 by exploiting XXE in conjunction with use of a Config API add-listener command to reach the RunExecutableListener class. Elasticsearch, although it uses Lucene, is NOT vulnerable to this. Note that the XML external entity expansion vulnerability occurs in the XML Query Parser which is available, by default, for any query request with parameters deftype=xmlparser and can be exploited to upload malicious data to the /upload request handler or as Blind XXE using ftp wrapper in order to read arbitrary local files from the Solr server. Note also that the second vulnerability relates to remote code execution using the RunExecutableListener available on all affected versions of Solr.

CVE-2017-9805 is an unsafe deserialization vulnerability in the REST plugin of Apache Struts 2, which uses the XStream library to deserialize XML request payloads without any type filtering. An attacker triggers it by sending a crafted XML payload to an endpoint handled by the REST plugin, causing the payload to be deserialized into arbitrary objects. Successful exploitation yields remote code execution on the server with the privileges of the web application, typically enough to fully take over the host. Struts 2.1.1 through 2.3.x before 2.3.34 and 2.5.x before 2.5.13 are affected, including products from Cisco and NetApp that bundle vulnerable Struts versions. The flaw has a public proof-of-concept exploit, is on CISA's Known Exploited Vulnerabilities catalog, and was reported as under active exploitation after its 2017 disclosure, although the Apache Foundation disputed suggestions that this specific flaw was used in the Equifax breach.

Do: Upgrade Apache Struts to 2.3.34, 2.5.13, or later, or apply the fixed updates for any Cisco or NetApp product that embeds Struts per their advisories. If patching is not immediate, remove or disable the REST plugin, or restrict the XML content types it accepts. Inventory internet-facing applications for Struts REST endpoints and hunt for suspicious XML POSTs, since the CVE is on the CISA KEV list and was reported as actively exploited.