FreeRTOS coreMQTT 5.0.0 out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability has been found in FreeRTOS coreMQTT 5.0.0 and classified as problematic. This affects an unknown part. Performing a manipulation results in out-of-bounds. This vulnerability is identified as CVE-2026-8686. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic has been found in FreeRTOS coreMQTT 5.0.0. This affects an unknown part. The manipulation with an unknown input leads to a out-of-bounds vulnerability. CWE is classifying the issue as CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. This is going to have an impact on availability. The summary by CVE is:

Missing bounds validation in the MQTT v5.0 property parser in coreMQTT before 5.0.1 allows an MQTT broker to cause a denial of service by sending a crafted packet. To remediate this issue, users should upgrade to v5.0.1.

The weakness was released by Epsilon as GHSA-6qh9-r6jp-2wxc. It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-8686 since 05/15/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 5.0.1 eliminates this vulnerability. The upgrade is hosted for download at github.com.

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Productinfo

Vendor

Name

Version

Website

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: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.1
NVD Vector: 🔒

CNA Base Score: 7.5
CNA Vector (AMZN): 🔒

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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: coreMQTT 5.0.1

Timelineinfo

05/15/2026 CVE reserved
05/16/2026 +1 days Advisory disclosed
05/16/2026 +0 days VulDB entry created
05/21/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-6qh9-r6jp-2wxc
Researcher: Epsilon
Status: Confirmed

CVE: CVE-2026-8686 (🔒)
GCVE (CVE): GCVE-0-2026-8686
GCVE (VulDB): GCVE-100-364311

Entryinfo

Created: 05/16/2026 06:56
Updated: 05/21/2026 10:31
Changes: 05/16/2026 06:56 (78), 05/21/2026 10:31 (11)
Complete: 🔍
Cache ID: 216::103

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