eprosima Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group)

Overview

eprosima Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group). Versions prior to 2.6.12, 2.14.6, 3.2.4, 3.3.1, and 3.4.2 have a remotely triggerable Out-of-Bounds Read while processing RTPS DATA_FRAG submessages. An attacker can craft a DATA_FRAG with a large sampleSize but a small actual payload, and set fragmentsInSubmessage such that the receiver treats the packet as the LAST fragment**. In this LAST-fragment path, Fast-DDS computes incoming_length based on sampleSize and calls memcpy() without validating incoming_data.length >= incoming_length. As a result, CacheChange_t::add_fragments() reads past the received UDP datagram buffer and into adjacent heap memory, copying those bytes into the reassembly buffer. In a Discovery Server deployment, the resulting CacheChange_t can be relayed to other participants, meaning that a newly joining participant may receive leaked heap memory (e.g., pointer values that could aid ASLR bypass). Versions 2.6.12, 2.14.6, 3.2.4, 3.3.1, and 3.4.2 fix the issue.

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.