How to fix the OpenSSL Critical vulnerability – OpenSSL 3.0.7  -Vulnerability Weekly special focus on application security

Critical Vulnerability affecting open source library OpenSSL - Application Security

Critical Vulnerability affecting open source library OpenSSL - Application Security
Critical Vulnerability affecting open source library OpenSSL – Application Security

On October 25, a critical vulnerability was announced for OpenSSL, with the fix and advisory on November 1st. This upcoming update will affect the application security and vulnerability management teams.

This is the second-rated critical vulnerability of the OpenSSL project 

The open SSL project team announced the release of a minor version to fix the vulnerability, but it will be available on the 1st of 2022. OpenSSL 3.0.7 will patch the critical vulnerability with the disclosure of the vulnerability.

Why a lot of attention and nervousness on this vulnerability? 

In 2014, the critical Heartbleed bug was announced and fixed; it became obvious how many systems depend on this vulnerability and how long it took for all the systems to be aligned to this new version. 

As OpenSSL is a widespread library, shown below is just a fraction of the direct usage: 

After log4j software composition analysis and infrastructure, the composition is ever more critical. 

The challenge with OpenSSL is that is nested in a lot of systems and a lot of libraries. 

So while you might be safe on an Operating system (not using openssl), the container that runs on it or the embedded software might expose and use

Controversial announcement

The patch for the critical vulnerability was announced on october 25th weeks before the official patch.


This allowed the team to gear up and prepare for fixes. There is a debate that this behaviour could trigger attackers to exploit the vulnerability 

System Affected

OpenSSL is included in many operating systems (Windows, macOS, various Linux distributions, etc.); client-side software; web and email server software (Apache, nginx, etc.); network appliances (Cisco, Fortinet, Juniper, etc.), industrial control systems, and so on.

Best defence

As this is an RCE, the best way to defend is to 

1 – create an inventory of all the systems that have open SSL installed and could have open SSL installed.

2 – fix as many instances as possible, prioritizing the one that can access easily

3 – for systems, repo that can’t be immediately fixed (vendors, SLA, maintenance), apply virtual patches on a WAF level to prevent specific strings from triggering the vulnerability. as there is no advisory in this space on the specific string, stay tuned for further updates

Challenges with those types of libraries

The challenge with open-source libraries, log4j, for example, is that a relatively small pool of people maintains them for free. This is quickly changing, with Google pledging large amounts of money to fix open-source libraries.

Key Point of this vulnerability:

  • The vulnerability seems to affect only OpenSSL 3.x releases, if you’re not using OpenSSL 3.x (ie, you’re still on OpenSSL 1.x across your org), you might be OK. Ensure your inventory is well maintained to determine whether you’re affected.
  • If you have systems which use OpenSSL 3.x that are Internet-facing or run critical functions (authn, authz), consider putting some mitigation in place ahead of this. Ex: if TLS termination occurs on a system which uses OpenSSL 3.x, consider delegating TLS termination to a system with a different TLS stack till you can patch.
  • If you have vendors who may use OpenSSL, now is the time to inquire whether they use 3.x releases and their errata schedule. Also list all the vendors that might have OpenSSL
use: openssl s_client -connect <domain name or IP>:<port>
  • Consider instituting a change freeze on/around November 1 to allow your teams the opportunity to build/test/release/patch as your highest priority if you’re using OpenSSL 3.x
  • OpenSSL is a library. Libraries can be linked to statically or dynamically. Consider how you would patch your systems in both cases.
  • * Any software upgrade, including dependent libraries, must go through testing. Complex distributed systems are hard. Make no assumptions about how a “trivial” patch may affect your systems.
  • * In case your systems use OpenSSL 3.x, how would you address static vs dynamically linked programs? What mitigation and patch strategies do you have?
  • What are your playbooks if a breach occurs prior to completing your mitigation or patch strategy? Work with your leadership team to understand your options for each scenario. Documenting scenarios and viable paths help to avoid rash decisions in stressful situations.
  • * During the log4j firefight, we saw numerous security commenters jump on the vulnerability, spreading misinformation and asking to remove libraries. 
  • This can cause a lot more pain, and removing a component can cause an enormous ripple effect. 
  • Fixing a vulnerability in code or on a system should always be staged, tested and verified with proper regression testing. Allow enough time for this implementing mitigating countermeasures like virtual patching.

Best of luck to all the security team and development team working on this

Previous Issues of vulnerability Weekly

Francesco is an internationally renowned public speaker, with multiple interviews in high-profile publications (eg. Forbes), and an author of numerous books and articles, who utilises his platform to evangelize the importance of Cloud security and cutting-edge technologies on a global scale.

Discuss this blog with our community on Slack

Join our AppSec Phoenix community on Slack to discuss this blog and other news with our professional security team

From our Blog

Contextual vulnerability management is a comprehensive approach to identifying, analyzing, and mitigating vulnerabilities in software and cloud infrastructure. It involves considering the specific context and environment in which vulnerabilities exist, including the software and hardware components, the network infrastructure, and the organizational policies and processes in place. By adopting this approach, organizations can more effectively assess and mitigate the risks posed by vulnerabilities, helping to protect their assets and maintain the security of their systems and networks.
Francesco Cipollone
Cyber security risk is challenging to calculate. Real-Time context, Cyber threat intelligence, Ownership Vulnerabilities, all part of the same continuum ->
Alfonso Eusebio
In today’s digital world, cyber threats are a real and growing concern for organizations of all sizes. As the threat landscape continues to evolve. we explore in this blog how to threat treats, which one to use in your prioritization strategy
Sally Turner

Join our Mailing list!

Get all the latest news, exclusive deals, and feature updates.

x Logo: ShieldPRO
This Site Is Protected By