---
type: concept
title: Email Security
tags: [security, email, encryption, authentication, privacy]
related: [smime, nutzerzertifikate, dfn-pki-zertifikate, phishing-prevention, unauthorized-email-clients, data-privacy-compliance]
created: 2026-06-30
updated: 2026-06-30
sources: ["output/rz_uni_greifswald_de_dienste_allgemein_e_mail_e_mail_sicherheit.md", "output/rz_uni_greifswald_de_dienste_allgemein_e_mail_e_mail_sicherheit_bedrohung_durch_.md", "output/rz_uni_greifswald_de_dienste_allgemein_e_mail_e_mail_sicherheit_cert.md", "output/rz_uni_greifswald_de_dienste_allgemein_e_mail_e_mail_sicherheit_unbefugte_accoun.md", "output/rz_uni_greifswald_de_dienste_allgemein_e_mail_e_mail_sicherheit--1yyygpb.md"]
---

# Email Security

Email security (E-Mail-Sicherheit) at the Universität Greifswald encompasses the set of practices, technical measures, and behavioral habits implemented to ensure the confidentiality, integrity, and authenticity of electronic communication, ensuring trustworthy and secure email communication within the university infrastructure.

## Technical Pillars of Secure Communication
According to the [[universitatsrechenzentrum-urz]], secure email transmission relies on primary technical pillars, often categorized as cryptographic protection:

### 1. Content Protection (Encryption)
Encryption is used to ensure that the contents of an email remain confidential and are protected from unauthorized access during transit. 
- This is primarily achieved through protocols like [[smime]].
- The use of [[smime]] ensures that only the intended recipient can read the content.

### 2. Sender Verification (Digital Signatures)
Digital signatures are used to verify the authenticity of an email, providing assurance that the message actually originates from the stated sender and has not been altered.
- **S/MIME:** Used to sign emails to verify the identity of the sender and ensure the message has not been altered.
- **Trust Anchor:** The [[universitatsrechenzentrum-urz]] explicitly states that only signed emails are trustworthy.
- **Identity Proof:** URZ staff utilize [[dfn-pki-zertifikate]] as a formal proof of identity.
- **Phishing Prevention:** Verifying authenticity is a core component used to prevent [[phishing-prevention]].

## Client Security and Data Sovereignty
A critical aspect of email security is ensuring that the software used to access email does not compromise user credentials or data sovereignty.

### Unauthorized Email Clients
The [[universitatsrechenzentrum-urz]] warns against using "spyware" clients that exfiltrate credentials and mirror mailboxes to external servers. Examples provided include:
- Edison Mail+
- Non-LTSC Outlook

## Implementation and Support
These security goals are realized through the use of [[nutzerzertifikate]] (user certificates) and the [[dfn-pki-zertifikate]] framework. The [[universitatsrechenzentrum-urz]] provides the necessary PKI infrastructure and configuration guides to enable these security features across supported email clients.

Technical support for implementing these security measures or reporting security incidents (such as phishing or unauthorized account access) is managed by the [[universitatsrechenzentrum-urz]] via:
- The [[groupware]] ticket system.
- The URZ hotline (ext. 1420).

## Threat Mitigation and Prevention
Security is maintained through a combination of software updates, behavioral strategies, and user vigilance.

### Software Hygiene and Configuration
- **Updates:** Regular security updates for browsers and plugins (e.g., Java) are mandatory for all operating systems (Windows, macOS, Linux).
- **Macro Security:** Disabling macros by default in Office applications prevents the execution of embedded malware.

### Data Protection
- **Data Redundancy:** To protect against ransomware, users are encouraged to store data on [[home-directory]] (central file servers), which utilize automatic snapshots for recovery.

### Behavioral Strategies and Monitoring
- **Phishing Prevention:** General security practices include [[phishing-prevention]] to identify and mitigate targeted email attacks, specifically by identifying "red flags" in sender addresses and file extensions.
- **Unauthorized Access:** Monitoring log data is used to detect credential exfiltration; password resets are required for compromised accounts.
- **VPN Interference:** It is noted that some antivirus VPNs (e.g., Norton) can cause false positives in security monitoring.

## Common Threats
- **Phishing:** Targeted credential theft (see [[phishing-prevention]]).
- **Ransomware:** Encryption of local data for ransom.
- **Malware:** Viruses and Trojans often delivered via `.exe`, `.msi`, or `.bat` attachments.