Vulnerability Scan Result
| Title: | ZAhN UG MailServer |
| Description: | No description found |
| ip_address | 87.139.170.30 |
| country | DE  |
| network_name | Deutsche Telekom AG |
| asn | AS3320 |
25/tcp | smtp | Postfix smtpd - |
80/tcp | http | nginx - |
110/tcp | pop3 | Dovecot pop3d - |
143/tcp | imap | Dovecot imapd - |
443/tcp | https | nginx - |
465/tcp | smtp | Postfix smtpd - |
587/tcp | smtp | Postfix smtpd - |
993/tcp | imaps | - - |
995/tcp | pop3s | - - |
| Software / Version | Category |
|---|---|
| DataTables 1.13.1 | JavaScript libraries |
| Bootstrap | UI frameworks |
| jQuery 3.6.0 | JavaScript libraries |
| Nginx | Web servers, Reverse proxies |
| Chart.js | JavaScript graphics |
| HSTS | Security |
Web Application Vulnerabilities
Evidence
| URL | Evidence |
|---|---|
| http://mta-sts.zahnug.de/ | Password input detected over insecure HTTP. Login form: ` |
Vulnerability description
We found that passwords are transmitted over a network without encryption. When users submit their passwords through an application or system, the lack of encryption means that the sensitive information is transmitted in plaintext, making it susceptible to interception and unauthorized access.
Risk description
The risk is that malicious actors could employ various techniques, such as packet sniffing or man-in-the-middle attacks, to capture plaintext passwords. Once intercepted, the attacker gains unauthorized access to user accounts, potentially leading to identity theft, unauthorized data access, or other malicious activities. The risk remains unchanged even if the password's form submission triggers a redirect response to an HTTPS page.
Recommendation
We recommend you to reconfigure the web server so it uses HTTPS - which encrypts the communication between the web browser and the server. This way, the attacker will not be able to obtain the clear-text passwords, even though he manages to intercept the network communication.
Classification
| CWE | CWE-523 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Evidence
| URL | Cookie Name | Evidence |
|---|---|---|
| http://mta-sts.zahnug.de/ | MCSESSID | Set-Cookie: MCSESSID=f0e7e1babe309775dcbb52a4792c735f |
Vulnerability description
We found that a cookie has been set without the Secure flag, which means the browser will send it over an unencrypted channel (plain HTTP) if such a request is made. The root cause for this usually revolves around misconfigurations in the code or server settings.
Risk description
The risk exists that an attacker will intercept the clear-text communication between the browser and the server and he will steal the cookie of the user. If this is a session cookie, the attacker could gain unauthorized access to the victim's web session.
Recommendation
Whenever a cookie contains sensitive information or is a session token, then it should always be passed using an encrypted channel. Ensure that the secure flag is set for cookies containing such sensitive information.
Classification
| CWE | CWE-614 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Evidence
| URL | Cookie Name | Evidence |
|---|---|---|
| http://mta-sts.zahnug.de/ | mailcow_locale | The server responded with Set-Cookie header(s) that does not specify the HttpOnly flag: Set-Cookie: mailcow_locale=bg-bg |
Vulnerability description
We found that a cookie has been set without the HttpOnly flag, which means it can be accessed by potentially malicious JavaScript code running inside the web page. The root cause for this usually revolves around misconfigurations in the code or server settings.
Risk description
The risk is that an attacker who injects malicious JavaScript code on the page (e.g. by using an XSS attack) can access the cookie and can send it to another site. In case of a session cookie, this could lead to session hijacking.
Recommendation
Ensure that the HttpOnly flag is set for all cookies.
Classification
| CWE | CWE-1004 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Evidence
| URL | Response URL | Evidence |
|---|---|---|
| http://mta-sts.zahnug.de/ | http://mta-sts.zahnug.de/ | Communication is made over unsecure, unencrypted HTTP. |
Vulnerability description
We noticed that the communication between the web browser and the server is done using the HTTP protocol, which transmits data unencrypted over the network.
Risk description
The risk is that an attacker who manages to intercept the communication at the network level can read and modify the data transmitted (including passwords, secret tokens, credit card information and other sensitive data).
Recommendation
We recommend you to reconfigure the web server to use HTTPS - which encrypts the communication between the web browser and the server.
Classification
| CWE | CWE-319 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Evidence
| URL | Method | Parameters | Evidence |
|---|---|---|---|
| http://mta-sts.zahnug.de/ | GET | Headers: User-Agent=Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36 | Error message mysql error found in: |
Vulnerability description
We noticed that the target application does not properly handle exceptional conditions, leading to error messages that reveal sensitive information.
Risk description
The risk is that an attacker may use the contents of error messages to help launch another, more focused attack. For example, an attempt to exploit a path traversal weakness (CWE-22) might yield the full pathname of the installed application.
Recommendation
It is recommended treating all exceptions of the application flow. Ensure that error messages only contain minimal details.
Classification
| CWE | CWE-209 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Evidence
Vulnerability description
We found the robots.txt on the target server. This file instructs web crawlers what URLs and endpoints of the web application they can visit and crawl. Website administrators often misuse this file while attempting to hide some web pages from the users.
Risk description
There is no particular security risk in having a robots.txt file. However, it's important to note that adding endpoints in it should not be considered a security measure, as this file can be directly accessed and read by anyone.
Recommendation
We recommend you to manually review the entries from robots.txt and remove the ones which lead to sensitive locations in the website (ex. administration panels, configuration files, etc).
Evidence
| URL | Evidence |
|---|---|
| http://mta-sts.zahnug.de/ | Response does not include the HTTP Content-Security-Policy security header or meta tag |
Vulnerability description
We noticed that the target application lacks the Content-Security-Policy (CSP) header in its HTTP responses. The CSP header is a security measure that instructs web browsers to enforce specific security rules, effectively preventing the exploitation of Cross-Site Scripting (XSS) vulnerabilities.
Risk description
The risk is that if the target application is vulnerable to XSS, lack of this header makes it easily exploitable by attackers.
Recommendation
Configure the Content-Security-Header to be sent with each HTTP response in order to apply the specific policies needed by the application.
Classification
| CWE | CWE-1021 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Evidence
| Software / Version | Category |
|---|---|
| DataTables 1.13.1 | JavaScript libraries |
| Bootstrap | UI frameworks |
| jQuery 3.6.0 | JavaScript libraries |
| Nginx | Web servers, Reverse proxies |
| Chart.js | JavaScript graphics |
| HSTS | Security |
Vulnerability description
We noticed that server software and technology details are exposed, potentially aiding attackers in tailoring specific exploits against identified systems and versions.
Risk description
The risk is that an attacker could use this information to mount specific attacks against the identified software type and version.
Recommendation
We recommend you to eliminate the information which permits the identification of software platform, technology, server and operating system: HTTP server headers, HTML meta information, etc.
Classification
| CWE | CWE-200 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Vulnerability description
We have noticed that the server is missing the security.txt file, which is considered a good practice for web security. It provides a standardized way for security researchers and the public to report security vulnerabilities or concerns by outlining the preferred method of contact and reporting procedures.
Risk description
There is no particular risk in not having a security.txt file for your server. However, this file is important because it offers a designated channel for reporting vulnerabilities and security issues.
Recommendation
We recommend you to implement the security.txt file according to the standard, in order to allow researchers or users report any security issues they find, improving the defensive mechanisms of your server.
Classification
| CWE | CWE-1188 |
| OWASP Top 10 - 2017 | |
| OWASP Top 10 - 2021 |
Infrastructure Vulnerabilities
Evidence
We managed to detect a publicly accessible Post Office Protocol (POP3) service. Starting Nmap ( https://nmap.org ) at 2026-04-17 04:46 EEST Nmap scan report for mta-sts.zahnug.de (87.139.170.30) Host is up. rDNS record for 87.139.170.30: mail.jgf.info
PORT STATE SERVICE VERSION 110/tcp filtered pop3
Service detection performed. Please report any incorrect results at https://nmap.org/submit/ . Nmap done: 1 IP address (1 host up) scanned in 2.69 seconds
Vulnerability description
We found that the Post Office Protocol (POP3) service is publicly accessible and doesn’t include STARTTLS capability. Email clients use the Post Office Protocol (POP) to download emails for user accounts. Some POP servers are initially set up to operate over an unsecured protocol. When email clients download email content through this plaintext protocol, it can pose a substantial risk to the organization's network, especially depending on which user account is set to receive the emails.
Risk description
Exposing this service online can enable attackers to conduct man-in-the-middle attacks, thereby gaining access to sensitive user credentials and the contents of emails. Given that POP3 operates via a plaintext protocol, the entirety of the data exchanged between the client and server is left unencrypted. This critical information could then be leveraged in further attacks on the organization's network.
Recommendation
We recommend turning off POP3 access over the Internet and instead using a Virtual Private Network (VPN) that mandates two-factor authentication (2FA). If the POP3 service is essential for business purposes, we recommend limiting access only from designated IP addresses using a firewall. Furthermore, activating STARTTLS capability (switching the connection to a secure communication) or utilizing Secure POP3 (POP3S) is recommended, as this protocol employs encryption.
Evidence
| Domain Queried | DNS Record Type | Description | Value |
|---|---|---|---|
| mta-sts.zahnug.de | A | IPv4 address | 87.139.170.30 |
Risk description
An initial step for an attacker aiming to learn about an organization involves conducting searches on its domain names to uncover DNS records associated with the organization. This strategy aims to amass comprehensive insights into the target domain, enabling the attacker to outline the organization's external digital landscape. This gathered intelligence may subsequently serve as a foundation for launching attacks, including those based on social engineering techniques. DNS records pointing to services or servers that are no longer in use can provide an attacker with an easy entry point into the network.
Recommendation
We recommend reviewing all DNS records associated with the domain and identifying and removing unused or obsolete records.