VDB-360202 · CVE-2026-7422 · EUVD-2026-26275

AWS FreeRTOS-Plus-TCP up to 4.2.5/4.4.0 Loopback Detection authentication spoofing

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.2	$0-$5k	0.00

Summaryinfo

A vulnerability labeled as critical has been found in AWS FreeRTOS-Plus-TCP up to 4.2.5/4.4.0. The impacted element is an unknown function of the component Loopback Detection. Executing a manipulation can lead to authentication spoofing. This vulnerability is tracked as CVE-2026-7422. The attack is only possible within the local network. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in AWS FreeRTOS-Plus-TCP up to 4.2.5/4.4.0 and classified as critical. This vulnerability affects an unknown part of the component Loopback Detection. The manipulation with an unknown input leads to a authentication spoofing vulnerability. The CWE definition for the vulnerability is CWE-290. This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Insufficient packet validation in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to bypass all checksum and minimum-size validation by spoofing the Ethernet source MAC address to match one of the device's own registered endpoints, because the loopback detection mechanism skips all input validation for packets whose source MAC matches a local endpoint. To mitigate this issue, users should upgrade to the fixed version when available.

The advisory is available at github.com. This vulnerability was named CVE-2026-7422 since 04/29/2026. The exploitation appears to be easy. The attack needs to be done within the local network. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

Upgrading to version 4.2.6 or 4.4.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-26275). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

FreeRTOS-Plus-TCP

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (AMZN): 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authentication spoofing
CWE: CWE-290 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: FreeRTOS-Plus-TCP 4.2.6/4.4.1

Timelineinfo

04/29/2026 Advisory disclosed
04/29/2026 +0 days CVE reserved
04/29/2026 +0 days VulDB entry created
04/29/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-7422 (🔒)
GCVE (CVE): GCVE-0-2026-7422
GCVE (VulDB): GCVE-100-360202
EUVD: 🔒

Entryinfo

Created: 04/29/2026 21:20
Updated: 04/29/2026 22:40
Changes: 04/29/2026 21:20 (76), 04/29/2026 22:40 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.