Well-known · Windows

135 MS RPC Endpoint Mapper

TCP Yes
UDP Yes
SCTP —
DCCP —

What it is

Microsoft EPMAP / DCE-RPC locator — clients ask it which dynamic port a service uses.

When / why

Core to AD, DCOM, WMI and Exchange. Internet-exposed 135 is a major risk; keep internal only.

Protocol status detail

TransportStatusMeaning
TCP Yes Assigned by IANA and standardized, specified, or widely used on this port.
UDP Yes Assigned by IANA and standardized, specified, or widely used on this port.
SCTP — Not applicable for this transport.
DCCP — Not applicable for this transport.
« 123 NTP 137 NetBIOS Name Service »

Port range

Well-known (0–1023). System port for a core service. On Unix-like systems, binding it requires superuser privileges.

Browse all ports →

Firewall rules for port 135

Copy-ready inbound rules for the active transports. Replace every <source> placeholder with the specific host, subnet, or CIDR that should reach this port.

ufw

sudo ufw allow proto tcp from <source> to any port 135

Allow TCP 135 (MS RPC Endpoint Mapper). Replace <source> with the network/host that should reach it.

sudo ufw allow proto udp from <source> to any port 135

Allow UDP 135 (MS RPC Endpoint Mapper). Replace <source> with the network/host that should reach it.

firewalld

sudo firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address="<source>" port port="135" protocol="tcp" accept'

Allow TCP 135 (MS RPC Endpoint Mapper) from <source>. Run 'firewall-cmd --reload' afterwards.

sudo firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address="<source>" port port="135" protocol="udp" accept'

Allow UDP 135 (MS RPC Endpoint Mapper) from <source>. Run 'firewall-cmd --reload' afterwards.

nftables

nft add rule inet filter input ip saddr <source> tcp dport 135 accept

Allow TCP 135 (MS RPC Endpoint Mapper). Assumes table 'inet filter' with an 'input' chain.

nft add rule inet filter input ip saddr <source> udp dport 135 accept

Allow UDP 135 (MS RPC Endpoint Mapper). Assumes table 'inet filter' with an 'input' chain.

iptables

sudo iptables -A INPUT -p tcp -s <source> --dport 135 -j ACCEPT

Allow TCP 135 (MS RPC Endpoint Mapper). Persist with iptables-save/netfilter-persistent.

sudo iptables -A INPUT -p udp -s <source> --dport 135 -j ACCEPT

Allow UDP 135 (MS RPC Endpoint Mapper). Persist with iptables-save/netfilter-persistent.

Azure NSG

az network nsg rule create -g <resource-group> --nsg-name <nsg> -n Allow-msrpcendpointmapper-135 --priority 1000 --access Allow --direction Inbound --protocol "*" --source-address-prefixes <source> --destination-port-ranges 135

Inbound rule for 135 (MS RPC Endpoint Mapper). Set <source> to a CIDR; lower priority number = higher precedence.

AWS Security Group

aws ec2 authorize-security-group-ingress --group-id <sg-id> --ip-permissions IpProtocol=tcp,FromPort=135,ToPort=135,IpRanges="[{CidrIp=<source-cidr>}]"

Inbound TCP 135 (MS RPC Endpoint Mapper). Replace <source-cidr> (e.g. 10.0.0.0/16).

aws ec2 authorize-security-group-ingress --group-id <sg-id> --ip-permissions IpProtocol=udp,FromPort=135,ToPort=135,IpRanges="[{CidrIp=<source-cidr>}]"

Inbound UDP 135 (MS RPC Endpoint Mapper). Replace <source-cidr> (e.g. 10.0.0.0/16).

GCP firewall

gcloud compute firewall-rules create allow-msrpcendpointmapper-135 --direction=INGRESS --action=ALLOW --rules=tcp:135,udp:135 --source-ranges=<source-cidr> --network=<network>

Ingress rule for 135 (MS RPC Endpoint Mapper). Scope with --source-ranges and optionally --target-tags.

Windows netsh

netsh advfirewall firewall add rule name="Allow MS RPC Endpoint Mapper 135/TCP" dir=in action=allow protocol=TCP localport=135 remoteip=<source>

Inbound TCP 135 (MS RPC Endpoint Mapper). Set remoteip to a host/subnet; 'any' is discouraged.

netsh advfirewall firewall add rule name="Allow MS RPC Endpoint Mapper 135/UDP" dir=in action=allow protocol=UDP localport=135 remoteip=<source>

Inbound UDP 135 (MS RPC Endpoint Mapper). Set remoteip to a host/subnet; 'any' is discouraged.

Windows PowerShell

New-NetFirewallRule -DisplayName "Allow MS RPC Endpoint Mapper 135/TCP" -Direction Inbound -Action Allow -Protocol TCP -LocalPort 135 -RemoteAddress <source>

Inbound TCP 135 (MS RPC Endpoint Mapper). Replace <source> with a host or subnet.

New-NetFirewallRule -DisplayName "Allow MS RPC Endpoint Mapper 135/UDP" -Direction Inbound -Action Allow -Protocol UDP -LocalPort 135 -RemoteAddress <source>

Inbound UDP 135 (MS RPC Endpoint Mapper). Replace <source> with a host or subnet.

Rules are generated only for transports marked active for this port. They default to an inbound allow with an explicit source placeholder — never any. Review direction, scope, and rule precedence before applying in production.