CVE-2021-38487Network attack vector

Denial of service via network amplification

Published May 5, 2022 · Updated Jun 23, 2025

Network amplification in RTI Connext Professional and Connext Micro allows remote attackers to interrupt service via specially crafted packets. The packet-processing path permits disproportionate response traffic and exposes information while flooding devices with unwanted messages. No authentication or user interaction is required, and the resulting impact is denial of service with limited information disclosure.

CVSS severity8.8
High
EPSS probability3.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Network amplification in RTI Connext Professional and Connext Micro allows remote attackers to interrupt service via specially crafted packets. The packet-processing path permits disproportionate response traffic and exposes information while flooding devices with unwanted messages. No authentication or user interaction is required, and the resulting impact is denial of service with limited information disclosure.

The record

CVE
CVE-2021-38487
Published
May 5, 2022
Updated
Jun 23, 2025
Vendor
Real-Time Innovations
Product
Connext Micro
Classifications
CWE-923, CWE-406, CAPEC-224, CAPEC-490, T1498
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 5, 2022CVE publishedPublication date reported by the CVE source.
  2. Jun 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.4.0 <2.4.*
  2. Affected versionversion=3.0.0 <3.0.*
  3. Affected versionversion=4.0.0 <4.0.*

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Real-Time Innovations · Connext Microversion=2.4.0 <2.4.*; version=3.0.0 <3.0.*; version=4.0.0 <4.0.*
Real-Time Innovations · Connext Professionalversion=4.1 <6.1.0

Published CVSS scores

8.2CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
8.8CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-923Improper Restriction of Communication Channel to Intended Endpoints
CWE-406Insufficient Control of Network Message Volume (Network Amplification)
CAPEC-224Fingerprinting
CAPEC-490Amplification
T1498Network Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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