CVE-2025-64438: Fast-DDS: Unbounded GAP range triggers OOM DoS under RELIABLE QoS

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-03 · updated 2026-06-17
Weakness: CWE-835

Description

Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group ). Prior to versions 3.4.1, 3.3.1, and 2.6.11, a remotely triggerable Out-of-Memory (OOM) denial-of-service exists in Fast -DDS when processing RTPS GAP submessages under RELIABLE QoS. By sending a tiny GAP packet with a huge gap range (`gapList .base - gapStart`), an attacker drives `StatefulReader::processGapMsg()` into an unbounded loop that inserts millions of s equence numbers into `WriterProxy::changes_received_` (`std::set`), causing multi-GB heap growth and process termination. No authentication is required beyond network reachability to the reader on the DDS domain. In environments without an RSS limit (non-ASan / unlimited), memory consumption was observed to rise to ~64 GB. Versions 3.4.1, 3.3.1, and 2.6.11 patch t he issue.

Affected products

eProsima Fast-DDS: before 2.6.11; from 3.0.0 before 3.3.1; 3.4.0 — fixed in 2.6.11, 3.3.1

How to fix

Upgrade to a fixed version: eProsima Fast-DDS 2.6.11, 3.3.1. Check the vendor advisory for mitigations.

References

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