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Mallory
HighPublic exploit

DoS in Siemens SIPROTEC EN100 Ethernet Module via UDP Port 50000

IdentifiersCVE-2015-5374CWE-20

CVE-2015-5374 is a denial-of-service vulnerability affecting Siemens SIPROTEC devices that use the EN100 Ethernet module, including firmware variants PROFINET IO, Modbus TCP, DNP3 TCP, IEC 104, and the EN100 module included in the SIPROTEC Merging Unit 6MU80. According to the provided content, specially crafted packets sent to UDP port 50000 can cause the affected device to enter an unresponsive state. Affected versions include PROFINET IO firmware for EN100 Ethernet module before V1.04.01, Modbus TCP firmware before V1.11.00, DNP3 TCP firmware before V1.03, IEC 104 firmware before V1.21, and EN100 Ethernet module in SIPROTEC Merging Unit 6MU80 before 1.02.02. The issue is described as being triggerable remotely over the network by malformed or specially crafted UDP traffic directed at the exposed service.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation causes denial of service of the affected SIPROTEC device or EN100 Ethernet module. The device may become unresponsive and service recovery may require a manual reboot. In operational technology and electric power environments, this can disable or hamper protective relay functionality and reduce availability of protection or control functions, potentially increasing operational risk during a broader intrusion or disruptive event.

Mitigation

If you can’t patch tonight, do this now.

If immediate patching is not possible, restrict network access to affected devices, especially UDP port 50000, to only strictly necessary management or engineering paths. Segment protection relays and related OT assets from untrusted or routable networks, enforce allowlisting at firewalls, and monitor for unexpected traffic to UDP/50000. Because exploitation is network-based and can render devices unresponsive, compensating controls should prioritize exposure reduction, strict access control between IT and OT zones, and detection of anomalous traffic targeting SIPROTEC devices.

Remediation

Patch, then assume compromise.

Apply Siemens firmware updates that address CVE-2015-5374. Based on the provided content, fixed versions are PROFINET IO for EN100 Ethernet module V1.04.01 or later, Modbus TCP for EN100 Ethernet module V1.11.00 or later, DNP3 TCP for EN100 Ethernet module V1.03 or later, IEC 104 for EN100 Ethernet module V1.21 or later, and SIPROTEC Merging Unit 6MU80 EN100 Ethernet module 1.02.02 or later. Follow Siemens advisory SCA-732541 and vendor guidance for upgrade planning in OT environments.
PUBLIC EXPLOITS

Exploits

1 valid exploit after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).

VALID 1 / 2 TOTALView more in app
CVE-2015-5374-DoS-PoCMaturityPoCFrameworkmetasploitVerified exploit

This repository provides two exploit implementations (Python script and Metasploit module) for CVE-2015-5374, a denial of service vulnerability affecting Siemens SIPROTEC 4 and SIPROTEC Compact EN100 Ethernet Modules with firmware versions below V4.25. The exploit works by sending a specially crafted UDP packet to port 50000 of the target device, causing it to crash and require a manual reboot. The Python script (Siemens_SIPROTEC_DoS.py) is a standalone exploit that takes the target IP as an argument and sends the malicious packet. The Metasploit module (siemens_siprotec4.rb) integrates with the Metasploit Framework, allowing for easier exploitation and automation. Both implementations use the same payload and target the same network vector. The repository is well-structured, with a README.md providing usage instructions, background, and references. No hardcoded IPs or domains are present; the only fingerprintable endpoint is the UDP port 50000 on the target device.

canDisclosed Feb 14, 2018pythonrubynetwork
EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType
SiemensSiprotec Firmwareoperating_system

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What this page doesn’t show

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware3

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity3

Community discussion across Reddit, Mastodon, and other social sources.