Improper Control of Dynamically-Managed Code Resources, Unrestricted Upload of File with Dangerous Type, Inclusion of Functionality from Untrusted Control Sphere vulnerability in Apache Solr.This issue affects Apache Solr: from 6.0.0 through 8.11.2, from 9.0.0 before 9.4.1. In the affected versions, Solr ConfigSets accepted Java jar and class files to be uploaded through the ConfigSets API. When backing up Solr Collections, these configSet files would be saved to disk when using the LocalFileSystemRepository (the default for backups). If the backup was saved to a directory that Solr uses in its ClassPath/ClassLoaders, then the jar and class files would be available to use with any ConfigSet, trusted or untrusted. When Solr is run in a secure way (Authorization enabled), as is strongly suggested, this vulnerability is limited to extending the Backup permissions with the ability to add libraries. Users are recommended to upgrade to version 8.11.3 or 9.4.1, which fix the issue. In thes…

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

The 8.1.1 and 8.2.0 releases of Apache Solr contain an insecure setting for the ENABLE_REMOTE_JMX_OPTS configuration option in the default solr.in.sh configuration file shipping with Solr. If you use the default solr.in.sh file from the affected releases, then JMX monitoring will be enabled and exposed on RMI_PORT (default=18983), without any authentication. If this port is opened for inbound traffic in your firewall, then anyone with network access to your Solr nodes will be able to access JMX, which may in turn allow them to upload malicious code for execution on the Solr server.

Apache Solr 5.0.0 to Apache Solr 8.3.1 are vulnerable to a Remote Code Execution through the VelocityResponseWriter. A Velocity template can be provided through Velocity templates in a configset `velocity/` directory or as a parameter. A user defined configset could contain renderable, potentially malicious, templates. Parameter provided templates are disabled by default, but can be enabled by setting `params.resource.loader.enabled` by defining a response writer with that setting set to `true`. Defining a response writer requires configuration API access. Solr 8.4 removed the params resource loader entirely, and only enables the configset-provided template rendering when the configset is `trusted` (has been uploaded by an authenticated user).

Core creation allows users to replace "trusted" configset files with arbitrary configuration Solr instances that (1) use the "FileSystemConfigSetService" component (the default in "standalone" or "user-managed" mode), and (2) are running without authentication and authorization are vulnerable to a sort of privilege escalation wherein individual "trusted" configset files can be ignored in favor of potentially-untrusted replacements available elsewhere on the filesystem.  These replacement config files are treated as "trusted" and can use "<lib>" tags to add to Solr's classpath, which an attacker might use to load malicious code as a searchComponent or other plugin. This issue affects all Apache Solr versions up through Solr 9.7.  Users can protect against the vulnerability by enabling authentication and authorization on their Solr clusters or switching to SolrCloud (and away from "FileSystemConfigSetService").  Users are also recommended to upgrade to Solr 9.8.0, which mitigates this…

Relative Path Traversal vulnerability in Apache Solr. Solr instances running on Windows are vulnerable to arbitrary filepath write-access, due to a lack of input-sanitation in the "configset upload" API.  Commonly known as a "zipslip", maliciously constructed ZIP files can use relative filepaths to write data to unanticipated parts of the filesystem.   This issue affects Apache Solr: from 6.6 through 9.7.0. Users are recommended to upgrade to version 9.8.0, which fixes the issue.  Users unable to upgrade may also safely prevent the issue by using Solr's "Rule-Based Authentication Plugin" to restrict access to the configset upload API, so that it can only be accessed by a trusted set of administrators/users.

Insecure Default Initialization of Resource vulnerability in Apache Solr. New ConfigSets that are created via a Restore command, which copy a configSet from the backup and give it a new name, are created without setting the "trusted" metadata. ConfigSets that do not contain the flag are trusted implicitly if the metadata is missing, therefore this leads to "trusted" ConfigSets that may not have been created with an Authenticated request. "trusted" ConfigSets are able to load custom code into classloaders, therefore the flag is supposed to only be set when the request that uploads the ConfigSet is Authenticated & Authorized. This issue affects Apache Solr: from 6.6.0 before 8.11.4, from 9.0.0 before 9.7.0. This issue does not affect Solr instances that are secured via Authentication/Authorization. Users are primarily recommended to use Authentication and Authorization when running Solr. However, upgrading to version 9.7.0, or 8.11.4 will mitigate this issue otherwise.

Improper Authentication vulnerability in Apache Solr. Solr instances using the PKIAuthenticationPlugin, which is enabled by default when Solr Authentication is used, are vulnerable to Authentication bypass. A fake ending at the end of any Solr API URL path, will allow requests to skip Authentication while maintaining the API contract with the original URL Path. This fake ending looks like an unprotected API path, however it is stripped off internally after authentication but before API routing. This issue affects Apache Solr: from 5.3.0 before 8.11.4, from 9.0.0 before 9.7.0. Users are recommended to upgrade to version 9.7.0, or 8.11.4, which fix the issue.

Insertion of Sensitive Information into Log File vulnerability in the Apache Solr Operator. This issue affects all versions of the Apache Solr Operator from 0.3.0 through 0.8.0. When asked to bootstrap Solr security, the operator will enable basic authentication and create several accounts for accessing Solr: including the "solr" and "admin" accounts for use by end-users, and a "k8s-oper" account which the operator uses for its own requests to Solr. One common source of these operator requests is healthchecks: liveness, readiness, and startup probes are all used to determine Solr's health and ability to receive traffic. By default, the operator configures the Solr APIs used for these probes to be exempt from authentication, but users may specifically request that authentication be required on probe endpoints as well. Whenever one of these probes would fail, if authentication was in use, the Solr Operator would create a Kubernetes "event" containing the username and password of the "…

Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Apache Solr.This issue affects Apache Solr: from 6.0.0 through 8.11.2, from 9.0.0 before 9.4.1. Solr Streaming Expressions allows users to extract data from other Solr Clouds, using a "zkHost" parameter. When original SolrCloud is setup to use ZooKeeper credentials and ACLs, they will be sent to whatever "zkHost" the user provides. An attacker could setup a server to mock ZooKeeper, that accepts ZooKeeper requests with credentials and ACLs and extracts the sensitive information, then send a streaming expression using the mock server's address in "zkHost". Streaming Expressions are exposed via the "/streaming" handler, with "read" permissions. Users are recommended to upgrade to version 8.11.3 or 9.4.1, which fix the issue. From these versions on, only zkHost values that have the same server address (regardless of chroot), will use the given ZooKeeper credentials and ACLs when connecting.