Scotti Fletcher

Certificate expiry monitoring in Oracle Cloud Infrastructure

I’m sure we’ve all experienced it, either as a user, or as a system administrator. You know, that important SSL certificate everyone forgot about so didn’t renew, and now has expired?

When an SSL/TLS certificate expires it can create a number of problems, including:

Users’ web browsers will display warning messages, indicating that the website’s connection is not secure. This can lead to a loss of trust and deter user engagement.
API clients will often refuse to establish a connection if an SSL certificate is not valid potentially disrupting crucial data exchanges and integrations.
Search engines may flag the site as unsafe, leading to a drop in rankings and reduced organic traffic.

Also regularly encountering certificate warnings conditions users to accept future certificate errors, which makes them more likely to accept an SSL certificate warning should they be targeted in a Man In The Middle Attack.

To avoid these issues, it’s important to have enough advance warning that a certificate is going to expire so you can obtain a new one, install, and test it thoroughly.

If you’re already using Domain Validated (DV) certificates, such as those issued by Let’s Encrypt you might want to consider my automated Let’s Encryption Solution. This solution automatically handles the entire certificate lifecycle using serverless functions inside OCI. For those who prefer to bring their own certificates, these can be imported into OCI’s certificate service.

As at June 2023, certificate expiry monitoring in OCI is primarily focused on certificates associated with Load Balancers. To improve monitoring, I’ve developed a serverless solution that examines all certificates expiration dates. The solution emits logs and sends email notifications, also allowing for customisable lead time to align with your organisation’s certificate procurement process. Logs can also be forwarded to your SIEM solution if required.

OCI IAM Domains User Access Review

One of the recent additions to Oracle Cloud Infrastructure (OCI) is IAM Domains. New OCI tenancies are provisioned with IAM Domains and at time of writing tenancies with IDCS instances are being migrated to IAM Domains.

I originally created Peek to create a visual representation of effective user permissions inside an OCI tenancy to assist with performing user access reviews. Excessive permissions and IAM misconfigurations are a common issue found in cloud environments that can lead to privilege escalation and/or unauthorised access to resources and data.

At time of writing the latest release of the OCI CLI now supports interacting with IAM Domain resources and so I have created a version of Peek that works with IAM domains.

Automating Security List Rule reviews in Oracle Cloud Infrastructure

If you’re running workloads in Oracle Cloud Infrastructure (OCI) then it’s likely you’ll be familiar with Virtual Cloud Network (VCN) resources such as Subnets, Route Tables, Gateways etc. These software defined components allow you to build networks in OCI for you to deploy and run your workloads.

Oracle has documentation that explains VCN access and security features which include things like Security Rules, Security Zones, Local and Network Firewalls, and IAM policies. Security rules are made up of Security Lists and Network Security Groups (NSG’s) and are a foundational element of every VCN and Subnet that you create. They define what traffic is allowed in and out of your subnets and what hosts can talk to one another. When you create a subnet a Security List is automatically created with some default rules:

When it comes to implementing network access controls, you can use Security Lists, Network Security Groups or both. They are virtual firewall features that control traffic at the packet level. I’ll be covering Network Security Group reviews in a later post as I want to focus on Security Lists, specifically how you can easily review and validate rules to ensure they align with your workload, organisational, security and compliance requirements.

Managing multiple Let’s Encrypt certificates with Oracle Cloud Infrastructure

In my previous post I explained how you can use Let’s Encrypt and Oracle Cloud Infrastructure (OCI) serverless functions to obtain a publicly signed SSL certificate, and automatically manage its renewal lifecycle. The solution works as expected; I have a Let’s Encrypt certificate for my website automatically renewing 30 days before expiry. If you haven’t read my previous post I’d recommend taking a look before following the setup outlined below as it covers how the solution works, and some prerequisites.

Having multiple workloads running in various OCI regions I started thinking about a more elegant way to provision certificates across multiple regions. Certificates stored in the certificate service are only available to resources in the same region and would have required a function to be deployed in each region, and for each SSL certificate required.

I’ve since updated the solution to address this requirement. It is now possible to provision certificates across multiple OCI regions using a single OCI Function application. I’ve also taken the opportunity to implement other features such as:

Loading a list of certificates you want to manage from a JSON file stored in Object Storage.
Adding support for wildcard SSL certificates.
Adding support for Subject Alternative Names (SAN) in addition to the CN name.
Adding support for the use of DNS zones and Vaults that reside in different regions to the OCI Function.

Adding support to specify which vault, and region to use for a given certificate ensures that workloads with strict cryptographic key material requirements can still benefit from this solution.

If you’ve already followed the instructions from my previous post, the solution will continue to work as described. The only limitation being that it’ll only work for a single certificate. By following the steps below you can easily upgrade to issuing multiple certificates. If you haven’t set anything up yet that’s also fine as I’ll be covering the full install again here.

Let’s Encrypt serverless automation with Oracle Cloud Infrastructure

Let’s Encrypt made its debut back in late 2015. It is a free Certificate Authority provided by the Internet Security Research Group. The goal was to support the adoption of SSL / TLS to ensure the privacy of information sent over the public Internet. Let’s Encrypt is now serving over 2.5M certificates per day.

If you’re reading this it’s likely you’ve had to deal with SSL certificates before. It’s also likely some of you will have investigated an outage, only to find that an SSL certificate expired somewhere that no one knew about. Certificate discovery, management, and renewal can be time consuming and not much fun.

Cloud providers have made this job easier with the introduction of certificate services that are able to issue public Domain Validation (DV) certificates. Oracle Cloud Infrastructure (OCI) currently allows you to create private Certificate Authorities (CA’s), private Certificates, and private Certificate Authority bundles. Private certificate resources are used to secure communication across a private network, where certificates can be installed and trusted to enable secure communication.

But what about publicly signed certs for users connecting over the Internet? Using a private OCI certificate will result in a “certificate not trusted” error in your web browser; this is where Let’s Encrypt comes in. I’m going to show you how to run a completely automated serverless Let’s Encrypt solution in your OCI tenancy to install and automatically renew certificates that show as trusted in your web browser.

Import Logs to Logging Analytics & Preserving Log Sources

In the world of cloud computing there are often multiple ways to achieve the same or similar result. In Oracle Cloud Infrastructure (OCI) logs are generated by the platform itself such as audit logs, OCI native services such as the Network Firewall Service, and custom logs from compute instances or your applications. These logs typically live in OCI logging where you can view them, or search them if required.

Collecting and storing logs is useful, however if you want to produce insights then you will need a way to analyse and visualise the log data. OCI Logging Analytics allows you to index, enrich, aggregate, explore, search, analyse, correlate, visualise and monitor all log data from your applications and system infrastructure.

From OCI logging there are two common ways in which logs can be ingested into Logging Analytics. The first is using a Service Connector to send logs to an Object Storage bucket, and an Object Collection Rule to then import the logs into Logging Analytics. The second option uses a Service Connector to send the logs directly to Logging Analytics. Both are valid options however require some consideration before use.

TLS Migration – A better way

HTTPS is essential as it protects the privacy of our data over the Internet. W3’s 2022 report shows nearly 80% of all websites use HTTPS as their default web protocol, up 6% on the previous year.

Getting started with HTTP/TLS is fairly straightforward. Obtain a CA signed certificate, configure it on your web servers and reverse proxy load balancers and you’re good to go. But how do you ensure your configuration stays up-to-date with current industry standards?

CyberSecurity is an arms race. As hardware and software evolves, so do the tools and techniques created to exploit them. This fierce race largely drives the innovation that we see in the industry today.

How does this relate to TLS? Since the inception of SSLv1 by Netscape in the 90’s there’s been many revisions, SSLv2, SSLv3, TLSv1.1, TLSv1.2 with the current version being TLSv1.3. TLSv1.1 was deprecated in 2021, with new versions being released approximately every 5 years. Given the rate at which exploits are discovered these release cycles will also need to keep pace.

For organisations this poses a number of interesting challenges because you can only control what TLS versions you support. Also if your website or API is public then it’s likely you have no control over the connecting client, or which TLS versions they’re able to use.

Virus & Malware Scanning Object Storage in OCI

If you’re like me, then working in IT means you also assume Tech Support duties for friends, family, and those distant relatives that only seem to call when they’ve got a problem.

I just clicked on this link, and my computer is doing something weird. I think my PC has a virus, what do I do?

When it’s just a single computer, the answer is simple, contain and validate the rouge software is removed, install an AV solution, change their passwords, enable MFA, and provide some education on what to look out for next time.

But now imagine you’re an organisation building a new application, or are moving applications to the cloud. Are you simply performing a lift-and-shift or are you planning to make use of cloud native services? Where are you going to store your data, specifically user uploaded files? Object Storage was built specifically to solve the challenges of how to store unstructured data in the cloud.

However, there is a catch. If you were previously storing files on a server file system, then it’s likely you were also running an anti-virus / anti-malware solution to identify malicious files. With Object Storage the underlying file system is transparent, so you can’t install AV, yet many compliance requirements still state “Uploaded files must be scanned for viruses and malware”.

OCI User Access Review Made Easy

I’m sure we can all agree, adopting a cloud strategy is awesome. The opportunities and benefits it affords are many. However cloud governance is an ongoing problem that plagues security, compliance, and management teams, which cloud vendors like Oracle are continually trying to solve.

If you’re reading this, you’ve probably been asked, or heard at least once:

Who has access to what in our environment?
Any Security / Compliance Manager

The answer should be easy and simple. However the reality is likely lots of manual time & work, spreadsheets, and endless clicking in a cloud console. If you’re doing this manually then I agree, it’s time that you could be dedicating to more important tasks.

The challenge in trying to answer these questions:

What users exist and what groups do they belong to?
What does my OCI tenancy compartment structure look like?
What policies have users explicitly created?
What permissions do users have in my tenancy?
Are there any excessive / non-compliant policies & permissions in my tenancy?

is that these complex relationships can’t be easily represented and interpreted in a table-like format. In the OCI ecosystem:

users can be federated with an Identity Provider and can belong to one or many federated, or local IAM groups,
policies can be defined for “any-user” or for a group,
policies are inherited meaning they apply to all sub-compartments from which the policies are applied.

To make things easier I’ve created a solution using Oracle tools and services to simplify the auditing of OCI tenancies and user permissions called “Peek”.

Note: If you have an OCI tenancy with IAM Domains instead of IDCS, use these instructions https://redthunder.blog/2023/03/20/oci-iam-domains-user-access-review/ instead of those below.

Note: From 22/05/2023 APEX is no longer required as the solution runs entirely inside the container. To run the new container for OCI with IDCS use the following command:

docker run -it --name peek --rm \
--mount type=bind,source=/Full/Path/To/.oci/,target=/root/.oci/,readonly \ -e OCI_PROFILE_NAME=<from your OCI config> \-e OCI_TENANCY_OCID=<from text file> \
-e OCI_IAM_URL=<from text file> \
-e IDCS_URL=<from text file> \
-e IDCS_CLIENT_ID=<from text file> \
-e IDCS_SECRET=<from text file> \-e TOOLTIP_LINE_PX=20 \
-p 4567:4567 \scottfletcher/oci-peek

After the docker container has started, you can access the web interface using the locally mapped port http://localhost:4567. You should see a progress window:

Once the mapping process is complete the visualisation will appear.

Depending on how long your policy statements are, you may wish to adjust TOOLTIP_LINE_PX to a number greater or smaller than 20. If your policy statements overflow the tooltip box then increase this value, or if the box is too big, then you can decrease this value.

If you haven’t run Peek before, please read on as I explain how to create the required credentials and where to obtain the values for the other environment variables. You can skip the APEX steps, as APEX will not be used.