CVE-2025-41676Public exploitNetwork attack vector

Device hang via unbounded send-sms request bursts

Published Jul 21, 2025 · Updated Nov 3, 2025

Resource exhaustion in REX 100 and mbNET.mini before 2.3.3 allows remote authenticated users to make the device unresponsive. The /cgi-bin/api.sh send_sms action processes bursts of crafted POST requests without adequately limiting critical resource consumption. High-privilege device credentials are required, and successful exploitation leaves the appliance unresponsive until reboot.

CVSS severity4.9
Medium
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in REX 100 and mbNET.mini before 2.3.3 allows remote authenticated users to make the device unresponsive. The /cgi-bin/api.sh send_sms action processes bursts of crafted POST requests without adequately limiting critical resource consumption. High-privilege device credentials are required, and successful exploitation leaves the appliance unresponsive until reboot.

The record

CVE
CVE-2025-41676
Published
Jul 21, 2025
Updated
Nov 3, 2025
Vendor
Helmholz GmbH & Co. KG
Product
REX 100
Classifications
CWE-400, T0814
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jul 21, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=0.0.0 <2.3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Helmholz GmbH & Co. KG · REX 100version=0.0.0 <2.3.3
MB connect line · mbNET.miniversion=0.0.0 <2.3.3

Published CVSS scores

4.9CERT@VDECVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T0814Denial of Service

Public exploit references

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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