CVE-2026-2674

Executive Summary

CVE-2026-2674 is a critical memory corruption vulnerability in RTI Connext Professional, affecting the Queueing Service, Core Libraries, and Persistence Service components. The vulnerability manifests as multiple out-of-bounds write conditions, allowing an attacker to overflow buffers and potentially achieve remote code execution or cause a denial of service. The flaw exists in versions prior to 6.1.*, 7.3.1.3, and 7.7.0. No public proof-of-concept or exploit code is currently available, but the high severity warrants immediate patching.

Supply Chain & Package Security

This vulnerability affects a proprietary middleware product (RTI Connext Professional) and is not distributed via public package registries like NPM or PyPI. Organizations using this software should verify their version and apply the vendor-supplied patches.

CVSS Breakdown & Threat Level

While the official CVSS vector is not provided, the vulnerability's nature (out-of-bounds write in network-facing services) suggests a high severity. A reasonable estimate would be:

• Attack Vector: Network (AV:N)
• Attack Complexity: Low (AC:L)
• Privileges Required: None (PR:N)
• User Interaction: None (UI:N)
• Scope: Unchanged (S:U)
• Confidentiality Impact: High (C:H)
• Integrity Impact: High (I:H)
• Availability Impact: High (A:H)
• Estimated CVSS Score: 9.8 (Critical)

Deep Dive & Mechanics

The vulnerability resides in the buffer management logic of RTI Connext Professional's core libraries and services. When processing specially crafted DDS (Data Distribution Service) messages, the software fails to validate the size of incoming data before writing it to a fixed-size buffer. This allows an attacker to send a message with a payload that exceeds the allocated buffer, causing a heap-based or stack-based buffer overflow.

The affected components (Queueing Service, Core Libraries, Persistence Service) handle data serialization and deserialization. The out-of-bounds write can corrupt adjacent memory structures, leading to:

• Overwriting function pointers or return addresses (code execution)
• Corrupting heap metadata (denial of service)
• Leaking sensitive memory contents (information disclosure)

The vulnerability is triggered by sending a malicious RTPS (Real-Time Publish-Subscribe) packet to a vulnerable service. No authentication is required, making it exploitable from the network.

Vulnerable vs. Patched Code

The vulnerable code likely resides in a function that copies data from a network buffer to an internal structure without proper bounds checking. A simplified example:

Vulnerable (pseudo-code):

void process_data(char *input, size_t input_len) {
    char buffer[256];
    // No bounds check
    memcpy(buffer, input, input_len);
}

Patched (pseudo-code):

void process_data(char *input, size_t input_len) {
    char buffer[256];
    if (input_len > sizeof(buffer)) {
        // Handle error
        return;
    }
    memcpy(buffer, input, input_len);
}

The actual patch involves adding size validation before memory copy operations in the affected components.

Exploitation & Lab Setup

Red Team

To simulate exploitation, set up a lab with:

• Target: RTI Connext Professional 7.0.0 (vulnerable)
• Attacker: Kali Linux with Python/scapy

1. Identify vulnerable service: Scan for RTI DDS services on port 7400 (default).
2. Craft malicious RTPS packet: Use a custom script to send an oversized payload.
3. Trigger overflow: Send the packet to the target service.

Example Python script (conceptual):

import socket

target_ip = "192.168.1.100"
target_port = 7400

# Craft oversized payload (simplified)
payload = b"A" * 1024  # Exceeds buffer size

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.sendto(payload, (target_ip, target_port))
sock.close()

Blue Team

• Monitor for anomalous DDS traffic: Look for packets with unusually large payloads.
• Enable logging: Configure RTI Connext to log buffer overflow attempts.
• Network segmentation: Isolate RTI services from untrusted networks.

Indicators of Compromise (IOCs)

• Network: UDP packets to/from port 7400 with payloads exceeding 256 bytes.
• Logs: RTI logs containing "buffer overflow" or "memory corruption" errors.
• Process: Unusual crashes or restarts of rti_connext processes.
• Memory: Heap corruption patterns in core dumps.

Detection Engineering

YARA Rule

rule CVE_2026_2674_RTI_Overflow {
    meta:
        description = "Detects RTI Connext Professional buffer overflow attempts"
        author = "Valters IT"
        date = "2026-03-15"
        reference = "CVE-2026-2674"
    strings:
        $s1 = "RTPS" ascii wide nocase
        $s2 = { 00 01 02 03 } // Example RTPS header bytes
    condition:
        $s1 at 0 and filesize > 1024
}

Sigma Rule

title: RTI Connext Professional Buffer Overflow Attempt
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects oversized UDP packets targeting RTI DDS services
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        DestinationPort: 7400
        Protocol: 'udp'
        PayloadLength: '> 256'
    condition: selection
falsepositives:
    - Legitimate large DDS messages (rare)
level: high

Suricata Rule

alert udp any any -> any 7400 (msg:"CVE-2026-2674 RTI Connext Professional Buffer Overflow Attempt"; content:"|00 01 02 03|"; depth:4; byte_test:1,>,256,4; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate: Upgrade to patched versions:
   • 6.1.* (latest 6.1.x)
   • 7.3.1.3
   • 7.7.0
2. Network: Restrict access to RTI services using firewalls.
3. Monitoring: Deploy the provided detection rules.
4. Workaround: If patching is not possible, disable the Queueing Service and Persistence Service if not required.

Valters IT
Securing Digital Frontiers