How to Respond to an Incident Involving an IP with a Bad Reputation

Detecting and Analyzing Entries in Web Server Logs

Question

During an incident, a cybersecurity analyst found several entries in the web server logs that are related to an IP with a bad reputation.

Which of the following would cause the analyst to further review the incident?

Answers

Explanations

Click on the arrows to vote for the correct answer

A. B. C. D. E.

E.

In this scenario, a cybersecurity analyst has found several entries in the web server logs that are related to an IP with a bad reputation. The analyst needs to further review the incident to determine if any malicious activity has taken place.

The web server logs contain information about the requests made to the server, including the IP address of the requesting client, the date and time of the request, the requested resource, and the response code.

Let's examine each of the log entries provided in the answer choices and identify any potentially suspicious activity:

A. BadReputationIp - - [2019-04-12 10:43Z] GET /etc/passwd 403 1023 This log entry shows a GET request to the /etc/passwd file, which is a commonly targeted file by attackers looking for user account information. The response code is 403, which means access to the resource was forbidden. This could indicate that the server is properly configured and access to sensitive resources is restricted.

B. BadReputationIp - - [2019-04-12 10:43Z] GET /index.html?src=../.ssh/id_rsa 401 17044 This log entry shows a GET request to the /index.html file with a query string parameter src=../.ssh/id_rsa, which could be an attempt to access a private key file. The response code is 401, which means the request requires authentication. This could indicate that the server is properly configured to require authentication for sensitive resources.

C. BadReputationIp - - [2019-04-12 10:43Z] GET /a.php?src=/etc/passwd 403 11056 This log entry shows a GET request to the /a.php file with a query string parameter src=/etc/passwd, which could be an attempt to access the /etc/passwd file. The response code is 403, which means access to the resource was forbidden. This could indicate that the server is properly configured and access to sensitive resources is restricted.

D. BadReputationIp - - [2019-04-12 10:43Z] GET /a.php?src=../../.ssh/id_rsa 200 15036 This log entry shows a GET request to the /a.php file with a query string parameter src=../../.ssh/id_rsa, which could be an attempt to access a private key file. The response code is 200, which means the request was successful. This could indicate that the server is not properly configured and access to sensitive resources is allowed.

E. BadReputationIp - - [2019-04-12 10:43Z] GET /favicon.ico?src=../usr/share/icons 200 19064 This log entry shows a GET request to the /favicon.ico file with a query string parameter src=../usr/share/icons, which could be an attempt to access icons files. The response code is 200, which means the request was successful. This could be a legitimate request.

Based on the analysis of the log entries, the analyst should further review options B and D. These log entries show requests with query string parameters that could be attempts to access sensitive resources. The response codes indicate that the requests were not successful or required authentication, but further investigation is needed to determine if any malicious activity has taken place.