R 0/tcp # Reservedr 0/udp # Reservedtcpmux 1/tcp # TCP Port Service Multiplexer One of original portmappers. SGI/IRIX is still using it, thus scans for it are probable attempts to locate IRIX targets. A 'HELP' request to it returns Irix host's service listings.tcpmux 1/udp # TCP Port Service Multiplexer One of original portmappers. SGI/IRIX is still using it, thus scans for it are probable attempts to locate IRIX targets.
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A 'HELP' request to it returns Irix host's service listings.compressnet 2/tcp # Management Utilitycompressnet 2/udp # Management Utilitycompressnet 3/tcp # Compression Processcompressnet 3/udp # Compression Processrje 5/tcp # Remote Job Entryrje 5/udp # Remote Job Entryecho 7/tcp # Echo Used to trouble-shoot remote TCP/IP stacks (telnet to remote echo port, then type. All keystrokes will echo back if target stack is working thru app layer. DOS Threat: Attackers use it to relay flooding data. If relayed to a network broadcast, entire subnet can flood. To a syslog-loghost, logs can flood. Returns it to whatever you forged as your source socket. Any data sent can flood, but looping data output ports (eg: chargen, time, daytime) create deadly streaming floods.
How to Fix High CPU Usage. High CPU usage can be indicative of several different problems. If a program is eating up your entire processor, there's a good chance that it's not behaving properly. A maxed-out CPU is also a sign of a virus.
Disable on all hosts; enable only for brief trouble-shooting. Echo 7/udp # Echo Used to trouble-shoot remote TCP/IP stacks (telnet to remote echo port, then type. All keystrokes will echo back if target stack is working thru app layer. DOS Threat: Attackers use it to relay flooding data. If relayed to a network broadcast, entire subnet can flood. To a syslog-loghost, logs can flood.
Returns it to whatever you forged as your source socket. Any data sent can flood, but looping data output ports (eg: chargen, time, daytime) create deadly streaming floods. Disable on all hosts; enable only for brief trouble-shooting. Discard 9/tcp # Discard Port equiv to /dev/null. Reads pkts, then discards them.
Allows knowledge the host is alive and processing pkts. Used while trouble-shooting local stack's transmit ability (telnet to discard on remote host, knowing all transmitted keystrokes will just be discarded. No worry of corrupting host processes). No threat, but block on hosts and perimeter network devices as general rule. Discard 9/udp # Discard Port equiv to /dev/null. Reads pkts, then discards them.
Allows knowledge the host is alive and processing pkts. Used while trouble-shooting local stack's transmit ability (telnet to discard on remote host, knowing all transmitted keystrokes will just be discarded. No worry of corrupting host processes). No threat, but block on hosts and perimeter network devices as general rule. Systat 11/tcp # Active Users Provides very useful info to attackers (host's usernames, login times, origination hosts, etc.). Disable this port on all hosts. Systat 11/udp # Active Users Provides very useful info to attackers (host's usernames, login times, origination hosts, etc.).
Disable this port on all hosts. Daytime 13/tcp # Daytime Returns the time of day in machine language; can return OS version. Provides host time, which can be useful in timing attacks. Also creates a DOS threat when its output is looped echo port (7). Disable this port on all hosts.
Daytime 13/udp # Daytime Returns the time of day in machine language; can return OS version. Provides host time, which can be useful in timing attacks. Also creates a DOS threat when its output is looped echo port (7). Disable this port on all hosts.
Netstat 15/tcp # Now Unassigned (was netstat) Netstat was similar to systat and is still active on some operating systems. Provides remote attackers info about the host and network (socket status, route tables, arp table, multicast group members, per- protocol stat's, interfaces status, etc.). Disable this port on all hosts. Netstat 15/udp # Now Unassigned (was netstat) Netstat was similar to systat and is still active on some operating systems. Provides remote attackers info about the host and network (socket status, route tables, arp table, multicast group members, per- protocol stat's, interfaces status, etc.). Disable this port on all hosts.
Qotd 17/tcp # Quote of the Day (QOTD) Used to receive remote QOTDs. Used for social engineering attacks, where users receive fake instructions to verify passwords, etc. Disable this port on all hosts. Qotd 17/udp # Quote of the Day (QOTD) Used to receive remote QOTDs. Used for social engineering attacks, where users receive fake instructions to verify passwords, etc. Disable this port on all hosts.
Msp 18/tcp # Message Send Protocolmsp 18/udp # Message Send Protocolchargen 19/tcp # Character Generator Used to trouble-shoot TCP/IP stacks. Generates random characters at a high rate. DOS Threat: Attackers will loop it to the echo port, creating a very effective host and subnet DOS. Disable this port on all hosts, enable only for brief trouble-shooting tests.chargen 19/udp # Character Generator Used to trouble-shoot TCP/IP stacks.
Generates random characters at a high rate. DOS Threat: Attackers will loop it to the echo port, creating a very effective host and subnet DOS. Disable this port on all hosts, enable only for brief trouble-shooting tests.ftp-data 20/tcp # Default FTP Data Transfer Port Is FTP service's default data transfer port; required inbound if internal users are allowed access to external FTP sites, yet open port poses a threat (hole for network mapping, etc).
Modern firewalls solve this by keeping it closed until a valid FTP session exists, then only opening it between those hosts. Control via a stateful-tracking firewall, do not simply open at perimeter.
Ftp-data 20/udp # Default FTP Data Transfer Port Is FTP service's default data transfer port; required inbound if internal users are allowed access to external FTP sites, yet open port poses a threat (hole for network mapping, etc). Modern firewalls solve this by keeping it closed until a valid FTP session exists, then only opening it between those hosts. Control via a stateful-tracking firewall, do not simply open at perimeter. Ftp-control 21/tcp # FTP Control Port Is FTP service control port. Firewall rules focus on this port, then open port 20 only when required for a data transfer.
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Security Concerns with FTP: - Cleartext, re-usable passwords - Portal for user account grinding - FTP Bounce, where attacker uses ftp's 'port' command to redirect the FTP transfer to a port & IP other than default port 20 on the FTP server. Attacks can include 'bouncing' internal network scans, email forging/flooding, etc. CERT Advisories: CA-97.16, CA-99.13 Disable port on non-FTP servers.
Open at perimeter only with static route to internal FTP server(s). Ftp-control/ftp 21/udp # FTP Control Port Is FTP service control port. Firewall rules focus on this port, then open port 20 only when required for a data transfer. Security Concerns with FTP: - Cleartext, re-usable passwords - Portal for user account grinding - FTP Bounce, where attacker uses ftp's 'port' command to redirect the FTP transfer to a port & IP other than default port 20 on the FTP server. Attacks can include 'bouncing' internal network scans, email forging/flooding, etc.
CERT Advisories: CA-97.16, CA-99.13 Disable port on non-FTP servers. Open at perimeter only with static route to internal FTP server(s)., ftpfile transfer controlssh 22/tcp # SSH Remote Login Protocolssh/pcanywherestat 22/udp # SSH Remote Login Protocol, pcAnywhere Status Default udp status port for v2.0 thru v7.51, plus CE. Versions v8+ on use tcp 5631 & udp 5632. Telnet 23/tcp # Telnet Standard for remote host admin. Security Concerns of Telnet: - Cleartext, re-usable passwords - Portal for user account grinding CERT Advisories: CA-89.03, CA-95.14 Replace with SSH on critical hosts. Telnet 23/udp # Telnet Standard for remote host admin. Security Concerns of Telnet: - Cleartext, re-usable passwords - Portal for user account grinding CERT Advisories: CA-89.03, CA-95.14 Replace with SSH on critical hosts.
Smtp/smtp 25/tcp # Simple Mail Transfer Used by mail servers to receive inbound email. Security Concerns: Email servers are complex engines, often run as root, and required open at most network perimeters.
Thus are popular for attackers and new DOS or intrusion hacks always being found. Disable on non-mail server hosts.
Hello guys i have a problem with cpu usage after upgrading to windows 10,after upgrading my OS to windows it was fine at 5 to 10mins. After that CPU usage went high 90 to 100% it wont go down. I didn't install anything except for chrome.i triedall the suggestions i've read in the MS Community but still no luck, my pc still running in high CPU usage even in idle i just upgraded my OS yesterday, and update all my drivers. Install Eset anti virus 9 and malwarebytes, Run some Deep scan and novirus/malwares found on my unit, then i uninstall the antivirus and malwarebytes reboot my PC tried the other suggestion the clean boot,but still no luck.here is the screen on my task manager when i open chrome or some apps my cpu usage will reach 100%. Hi Kawi,Thank you for posting your query on Microsoft Community.I understand that you are facing issues with Windows 10. I apologize for the inconvenience caused to you.The issue could occur if some processes is consuming cpu process.To assist you better, please provide the information:.
Are you getting any error message?. Have you check which processes is consuming CPU memory?Refer to the below methods and check if it helps.Method 1: I suggest you to perform the system maintenance troubleshooter. It will resolve the common system problems.1. Click on search box next to Start Menu.2. Type “ Troubleshooting” without the quotes and click on Troubleshooting.3. Then click on System and Security.4.
Click on System Maintenance.5. Click on Next and follow the prompts to run the troubleshooter.If the issue still persist, refer to the below method.Method 2: I would suggest you to boot the Computer in Safe Mode and check if the issues is occurring or not. After following the below steps from the link. Under the options. Please select Safe Mode.If the issue still persist, refer to the below method.Method 3: I suggest you to run the Memory diagnostic tool and check the status of the System memory.1.
On the search bar, type “ Windows Memory Diagnostic” without the quotes and click on it.2. Click on Restart now and check for problems.3. Follow the instructions.Reply to us with the information, so that we can assist you better.Let us know if you need any further assistance on Windows related issues and we will be glad to help. Hi Kawi,Thank you for posting your query on Microsoft Community.I understand that you are facing issues with Windows 10. I apologize for the inconvenience caused to you.The issue could occur if some processes is consuming cpu process.To assist you better, please provide the information:.
Are you getting any error message?. Have you check which processes is consuming CPU memory?Refer to the below methods and check if it helps.Method 1: I suggest you to perform the system maintenance troubleshooter. It will resolve the common system problems.1.
Click on search box next to Start Menu.2. Type “ Troubleshooting” without the quotes and click on Troubleshooting.3. Then click on System and Security.4. Click on System Maintenance.5. Click on Next and follow the prompts to run the troubleshooter.If the issue still persist, refer to the below method.Method 2: I would suggest you to boot the Computer in Safe Mode and check if the issues is occurring or not. After following the below steps from the link.
Under the options. Please select Safe Mode.If the issue still persist, refer to the below method.Method 3: I suggest you to run the Memory diagnostic tool and check the status of the System memory.1. On the search bar, type “ Windows Memory Diagnostic” without the quotes and click on it.2.
Click on Restart now and check for problems.3. Follow the instructions.Reply to us with the information, so that we can assist you better.Let us know if you need any further assistance on Windows related issues and we will be glad to help.Hello there, this are the results after i follow method 1 2 and 3, and about 3 im confuse which one to click for the result. Only in method cpu usage went down but still high with no apps open at 56% cpu usage. The issue still there:(Method 1 Result:Method 2 Result:Method 3 Result.
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January 2023
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