Vulnerabilities > CVE-2017-12741 - Resource Exhaustion vulnerability in Siemens products
Summary
A vulnerability has been identified in Development/Evaluation Kits for PROFINET IO: DK Standard Ethernet Controller, Development/Evaluation Kits for PROFINET IO: EK-ERTEC 200, Development/Evaluation Kits for PROFINET IO: EK-ERTEC 200P, SIMATIC Compact Field Unit, SIMATIC ET200AL, SIMATIC ET200M (incl. SIPLUS variants), SIMATIC ET200MP IM155-5 PN BA (incl. SIPLUS variants), SIMATIC ET200MP IM155-5 PN HF (incl. SIPLUS variants), SIMATIC ET200MP IM155-5 PN ST (incl. SIPLUS variants), SIMATIC ET200S (incl. SIPLUS variants), SIMATIC ET200SP IM155-6 PN BA (incl. SIPLUS variants), SIMATIC ET200SP IM155-6 PN HA (incl. SIPLUS variants), SIMATIC ET200SP IM155-6 PN HF (incl. SIPLUS variants), SIMATIC ET200SP IM155-6 PN HS (incl. SIPLUS variants), SIMATIC ET200SP IM155-6 PN ST (incl. SIPLUS variants), SIMATIC ET200ecoPN, 16DI, DC24V, 8xM12, SIMATIC ET200ecoPN, 16DO DC24V/1,3A, 8xM12, SIMATIC ET200ecoPN, 4AO U/I 4xM12, SIMATIC ET200ecoPN, 8 DIO, DC24V/1,3A, 8xM12, SIMATIC ET200ecoPN, 8 DO, DC24V/2A, 8xM12, SIMATIC ET200ecoPN, 8AI RTD/TC 8xM12, SIMATIC ET200ecoPN, 8AI; 4 U/I; 4 RTD/TC 8xM12, SIMATIC ET200ecoPN, 8DI, DC24V, 4xM12, SIMATIC ET200ecoPN, 8DI, DC24V, 8xM12, SIMATIC ET200ecoPN, 8DO, DC24V/0,5A, 4xM12, SIMATIC ET200ecoPN, 8DO, DC24V/1,3A, 4xM12, SIMATIC ET200ecoPN, 8DO, DC24V/1,3A, 8xM12, SIMATIC ET200ecoPN: IO-Link Master, SIMATIC ET200pro, SIMATIC PN/PN Coupler (incl. SIPLUS NET variants), SIMATIC S7-1200 CPU family (incl. SIPLUS variants), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants), SIMATIC S7-1500 Software Controller, SIMATIC S7-200 SMART, SIMATIC S7-300 CPU family (incl. related ET200 CPUs and SIPLUS variants), SIMATIC S7-400 H V6 CPU family and below (incl. SIPLUS variants), SIMATIC S7-400 PN/DP V6 CPU family and below (incl. SIPLUS variants), SIMATIC S7-400 PN/DP V7 CPU family (incl. SIPLUS variants), SIMATIC S7-410 V8 CPU family (incl. SIPLUS variants), SIMATIC TDC CP51M1, SIMATIC TDC CPU555, SIMATIC WinAC RTX (F) 2010, SIMOCODE pro V EIP (incl. SIPLUS variants), SIMOCODE pro V PN (incl. SIPLUS variants), SIMOTION C, SIMOTION D (incl. SIPLUS variants), SIMOTION D4xx V4.4 for SINAMICS SM150i-2 w. PROFINET (incl. SIPLUS variants), SIMOTION P V4.4 and V4.5, SIMOTION P V5, SINAMICS DCM w. PN, SINAMICS DCP w. PN, SINAMICS G110M w. PN, SINAMICS G120(C/P/D) w. PN (incl. SIPLUS variants), SINAMICS G130 V4.7 w. PN, SINAMICS G130 V4.8 w. PN, SINAMICS G150 V4.7 w. PN, SINAMICS G150 V4.8 w. PN, SINAMICS GH150 V4.7 w. PROFINET, SINAMICS GL150 V4.7 w. PROFINET, SINAMICS GM150 V4.7 w. PROFINET, SINAMICS S110 w. PN, SINAMICS S120 V4.7 SP1 w. PN (incl. SIPLUS variants), SINAMICS S120 V4.7 w. PN (incl. SIPLUS variants), SINAMICS S120 V4.8 w. PN (incl. SIPLUS variants), SINAMICS S120 prior to V4.7 w. PN (incl. SIPLUS variants), SINAMICS S150 V4.7 w. PN, SINAMICS S150 V4.8 w. PN, SINAMICS SL150 V4.7.0 w. PROFINET, SINAMICS SL150 V4.7.4 w. PROFINET, SINAMICS SL150 V4.7.5 w. PROFINET, SINAMICS SM120 V4.7 w. PROFINET, SINAMICS V90 w. PN, SINUMERIK 840D sl, SIRIUS Soft Starter 3RW44 PN. Specially crafted packets sent to port 161/udp could cause a Denial-of-Service condition. The affected devices must be restarted manually.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- XML Ping of the Death An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.
- XML Entity Expansion An attacker submits an XML document to a target application where the XML document uses nested entity expansion to produce an excessively large output XML. XML allows the definition of macro-like structures that can be used to simplify the creation of complex structures. However, this capability can be abused to create excessive demands on a processor's CPU and memory. A small number of nested expansions can result in an exponential growth in demands on memory.
- Inducing Account Lockout An attacker leverages the security functionality of the system aimed at thwarting potential attacks to launch a denial of service attack against a legitimate system user. Many systems, for instance, implement a password throttling mechanism that locks an account after a certain number of incorrect log in attempts. An attacker can leverage this throttling mechanism to lock a legitimate user out of their own account. The weakness that is being leveraged by an attacker is the very security feature that has been put in place to counteract attacks.
- Violating Implicit Assumptions Regarding XML Content (aka XML Denial of Service (XDoS)) XML Denial of Service (XDoS) can be applied to any technology that utilizes XML data. This is, of course, most distributed systems technology including Java, .Net, databases, and so on. XDoS is most closely associated with web services, SOAP, and Rest, because remote service requesters can post malicious XML payloads to the service provider designed to exhaust the service provider's memory, CPU, and/or disk space. The main weakness in XDoS is that the service provider generally must inspect, parse, and validate the XML messages to determine routing, workflow, security considerations, and so on. It is exactly these inspection, parsing, and validation routines that XDoS targets. There are three primary attack vectors that XDoS can navigate Target CPU through recursion: attacker creates a recursive payload and sends to service provider Target memory through jumbo payloads: service provider uses DOM to parse XML. DOM creates in memory representation of XML document, but when document is very large (for example, north of 1 Gb) service provider host may exhaust memory trying to build memory objects. XML Ping of death: attack service provider with numerous small files that clog the system. All of the above attacks exploit the loosely coupled nature of web services, where the service provider has little to no control over the service requester and any messages the service requester sends.