Port 995 – POP3S Protocol Specification

Technical analysis, security advisories, vulnerability mitigation, and firewall syntax for TCP/UDP port 995 (POP3S).

Port Number 995

Transport Protocol TCP

Port Range Type Well-Known (0-1023)

Default Status Restricted / LAN

Service Description & Architectural Context

Post Office Protocol v3 over SSL/TLS for secure mailbox retrieval.

IANA / RFC Designation:

Port 995 is assigned to POP3S under the Internet Assigned Numbers Authority (IANA) service name registry. In enterprise infrastructure and homelab setups, services listening on this port must follow the principle of least privilege.

Security Analysis & Attack Surface Assessment

Secure replacement for legacy port 110.

Hardening Recommendations:

Do not expose port 995 to public WAN interfaces unless authenticated TLS or VPN wrapping is strictly enforced.
Enforce rate-limiting using Fail2ban, CrowdSec, or cloud edge DDoS protection.
Audit active listening sockets locally: ss -tulpn | grep :995 or netstat -ano | findstr :995.

Firewall Rule Snippets for Port 995

UFW (Ubuntu / Debian Linux)

sudo ufw allow 995/tcp

iptables (Standard Linux Kernel)

sudo iptables -A INPUT -p tcp --dport 995 -j ACCEPT

Windows PowerShell (Defender Advanced Firewall)

New-NetFirewallRule -DisplayName "Allow Port 995" -Direction Inbound -LocalPort 995 -Protocol TCP -Action Allow

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