Port 502 Details
known port assignments and vulnerabilities
3 records found
||Phoenix Contact FL IL 24 BK-PAC allows remote attackers to cause a denial of service (hang) via unspecified manipulations as demonstrated by a Nessus scan or (2) malformed input to TCP port 502.
The modbus_125_handler function in the Schneider Electric Quantum Ethernet Module on the NOE 771 device (aka the Quantum 140NOE771* module) allows remote attackers to install arbitrary firmware updates via a MODBUS 125 function code to TCP port 502.
Unspecified vulnerability in the Modbus/TCP Diagnostic function in MiniHMI.exe for the Automated Solutions Modbus Slave ActiveX Control before 1.5 allows remote attackers to corrupt the heap and possibly execute arbitrary code via malformed Modbus requests to TCP port 502.
References: [CVE-2007-4827] [BID-25713] [OSVDB-38259]
Triangle Research International (aka Tri) Nano-10 PLC devices with firmware before r81 use an incorrect algorithm for bounds checking of data in Modbus/TCP packets, which allows remote attackers to cause a denial of service (networking outage) via a crafted packet to TCP port 502.
Triangle Research International (aka Tri) Nano-10 PLC devices with firmware r81 and earlier do not properly handle large length values in MODBUS data, which allows remote attackers to cause a denial of service (transition to the interrupt state) via a crafted packet to TCP port 502.
References: [CVE-2013-5741], [OSVDB-97728], [SECUNIA-55782]
Schneider Electric Modicon TM221CE16R 188.8.131.52 devices allow remote attackers to discover the application-protection password via a \x00\x01\x00\x00\x00\x05\x01\x5a\x00\x03\x00 request to the Modbus port (502/tcp). Subsequently the application may be arbitrarily downloaded, modified, and uploaded.
References: [CVE-2017-7575], [BID-97523]
asa-appl-proto (IANA official)
||Modbus, Protocol (unofficial)
« back to SG Ports
SANS Internet Storm Center: port 502
Well Known Ports: 0 through 1023.
Registered Ports: 1024 through 49151.
Dynamic/Private : 49152 through 65535.
TCP ports use the Transmission Control Protocol. TCP is the most commonly used protocol
on the Internet and any TCP/IP network. Whereas the IP protocol deals only with packets, TCP enables two hosts
to establish a connection and exchange streams of data. TCP guarantees delivery of data
and that packets will be delivered in the same order in which they were sent.
Guaranteed communication/delivery is the key difference between TCP and UDP.
UDP ports use the Datagram Protocol, a communications protocol for the Internet network,
transport, and session layers. Like TCP (Transmission Control Protocol),
UDP is used with IP (the Internet Protocol) and makes possible the transmission of datagrams
from one computer to applications on another computer, but unlike TCP, UDP is connectionless
and does not guarantee reliable communication; it's up to the application that received
the message to process any errors and verify correct delivery. UDP is often used with time-sensitive
applications, such as audio/video streaming, where dropping some packets is preferable to waiting for delayed data.
When troubleshooting unknown open ports, it is useful to find exactly what services/processes are listening to them.
This can be accomplished in both Windows command prompt and Linux variants using the "netstat -aon" command.
We also recommend runnig multiple anti-virus/anti-malware scans to rule out the possibility of active malicious software.
For more detailed and personalized help please use our forums.
Please use the "Add Comment" button below to provide additional information or comments about port 502.