AWS FreeRTOS-Plus-TCP up to 4.2.5/4.4.0 integer underflow

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in AWS FreeRTOS-Plus-TCP up to 4.2.5/4.4.0. The affected element is an unknown function. Performing a manipulation results in integer underflow. This vulnerability is identified as CVE-2026-7424. The attack can only be performed from the local network. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in AWS FreeRTOS-Plus-TCP up to 4.2.5/4.4.0. This affects some unknown functionality. The manipulation with an unknown input leads to a integer underflow vulnerability. CWE is classifying the issue as CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. This is going to have an impact on integrity, and availability. The summary by CVE is:

Integer underflow in the DHCPv6 sub-option parser in FreeRTOS-Plus-TCP before V4.4.1 and V4.2.6 allows an adjacent network actor to corrupt the device's IPv6 address assignment, DNS configuration, and lease times, and to cause a denial of service (permanent IP task freeze requiring hardware reset) by sending a single crafted DHCPv6 packet. The issue is present whenever DHCPv6 is enabled. To mitigate this issue, users should upgrade to version V4.2.6 or V4.4.1 or newer.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-7424 since 04/29/2026. The exploitability is told to be easy. The attack can only be initiated within the local network. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly 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-2026-26277). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

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: 6.7
VulDB Meta Temp Score: 6.6

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.1
CNA Vector (AMZN): 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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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-2026-7424 (🔒)
GCVE (CVE): GCVE-0-2026-7424
GCVE (VulDB): GCVE-100-360201
EUVD: 🔒

Entryinfo

Created: 04/29/2026 21:19
Updated: 04/29/2026 22:40
Changes: 04/29/2026 21:19 (74), 04/29/2026 22:40 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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