CVE-2022-27772

Ein lokaler Angreifer kann eine Schwachstelle in VMware Tanzu Spring Boot ausnutzen, um seine Privilegien zu erhöhen.

Ein Angreifer kann mehrere Schwachstellen in Dell Data Protection Advisor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand herbeizuführen, Dateien zu manipulieren, vertrauliche Informationen offenzulegen, seine Berechtigungen zu erweitern oder einen nicht spezifizierten Angriff durchzuführen.

spring-boot versions prior to version `v2.2.11.RELEASE` was vulnerable to temporary directory hijacking. This vulnerability impacted the `org.springframework.boot.web.server.AbstractConfigurableWebServerFactory.createTempDir` method. The vulnerable method is used to create a work directory for embedded web servers such as Tomcat and Jetty. The directory contains configuration files, JSP/class files, etc. If a local attacker got the permission to write in this directory, they could completely take over the application (ie. local privilege escalation). #### Impact Location This vulnerability impacted the following source location: ```java /** * Return the absolute temp dir for given web server. * @param prefix server name * @return the temp dir for given server. */ protected final File createTempDir(String prefix) { try { File tempDir = File.createTempFile(prefix + ".", "." + getPort()); tempDir.delete(); tempDir.mkdir(); tempDir.deleteOnExit(); return tempDir; } ``` \- https://github.com/spring-projects/spring-boot/blob/ce70e7d768977242a8ea6f93188388f273be5851/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/server/AbstractConfigurableWebServerFactory.java#L165-L177 This vulnerability exists because `File.mkdir` returns `false` when it fails to create a directory, it does not throw an exception. As such, the following race condition exists: ```java File tmpDir =File.createTempFile(prefix + ".", "." + getPort()); // Attacker knows the full path of the file that will be generated // delete the file that was created tmpDir.delete(); // Attacker sees file is deleted and begins a race to create their own directory before Jetty. // and make a directory of the same name // SECURITY VULNERABILITY: Race Condition! - Attacker beats java code and now owns this directory tmpDir.mkdirs(); // This method returns 'false' because it was unable to create the directory. No exception is thrown. // Attacker can write any new files to this directory that they wish. // Attacker can read any files created by this process. ``` ### Prerequisites This vulnerability impacts Unix-like systems, and very old versions of Mac OSX and Windows as they all share the system temporary directory between all users. ### Patches This vulnerability was inadvertently fixed as a part of this patch: https://github.com/spring-projects/spring-boot/commit/667ccdae84822072f9ea1a27ed5c77964c71002d This vulnerability is patched in versions `v2.2.11.RELEASE` or later. ### Workarounds Setting the `java.io.tmpdir` system environment variable to a directory that is exclusively owned by the executing user will fix this vulnerability for all operating systems.