---
cve: "CVE-2026-8741"
severity: "LOW"
cvss: 2.3
epss: "0.4%"
vendor: "n/a"
kev: false
exploited: false
published: "2026-05-17 08:15:08"
tags: [cve, security, low]
source: tsecurity.de CVE-Dossier
exported: "2026-11-09T04:42:21+01:00"
---

# CVE-2026-8741

> 2.3 LOW · 🧪 PoC

## Beschreibung

A vulnerability has been found in EMQX up to 6.2.0. This affects an unknown function of the file apps/emqx/src/emqx_persistent_session_ds.erl of the component QoS 2 PUBLISH Packet Handler. Such manipulation leads to race condition. The attack may be performed from remote. A high complexity level is associated with this attack. The exploitability is reported as difficult. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure.

## CNA-Record (Kanon, cvelistV5)

- CNA: **VulDB**
- State: PUBLISHED
- Stand: 2026-05-18 17:53:07
- CNA-CVSS: **2.3** (`CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **poc**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |

## Schwachstellen-Klasse

- **CWE-362** — Concurrent Execution using Shared Resource with Improper Synchronization
  The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

## Angriffsmuster (CAPEC)

- [CAPEC-26 — Leveraging Race Conditions](https://capec.mitre.org/data/definitions/26.html) _(Severity: High)_
- [CAPEC-29 — Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions](https://capec.mitre.org/data/definitions/29.html) _(Severity: High)_

## Referenzen

- <https://vuldb.com/vuln/364329>
- <https://vuldb.com/vuln/364329/cti>
- <https://vuldb.com/submit/809931>
- <https://github.com/Pathfind-tama/Report_EMQX_MQTT>
- <https://github.com/Pathfind-tama/Report_EMQX_MQTT/blob/main/MQTT%20QoS%202%20Message%20Duplication%20in%20Persistent%20Sessions.md>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-8741/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_