CVE-2021-25274

The Collector Service in SolarWinds Orion Platform before 2020.2.4 uses MSMQ (Microsoft Message Queue) and doesnt set permissions on its private queues. As a result, remote unauthenticated clients can send messages to TCP port 1801 that the Collector Service will process. Additionally, upon processing of such messages, the service deserializes them in insecure manner, allowing remote arbitrary code execution as LocalSystem.

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

Potential Mitigations

• Make fields transient to protect them from deserialization.
• An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/586.html

References

• https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/full-system-control-with-new-solarwinds-orion-based-and-serv-u-ftp-vulnerabilities/
• https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/full-system-control-with-new-solarwinds-orion-based-and-serv-u-ftp-vulnerabilities/