Overview of ‘Backporting’ in Cyber Security
Backporting is the process of taking security patches, bug fixes, or feature updates from a newer version of software and applying them to an older version that is still in use. This is often necessary when organizations rely on legacy systems that cannot be upgraded to the latest version due to compatibility, operational, or dependency constraints.
Common scenarios where backporting is used:
1. Security Patching in Legacy Systems
Scenario: An organization is running CentOS 7, which includes an older version of OpenSSL. A critical vulnerability (e.g., Heartbleed) is discovered, but upgrading to the latest OpenSSL version would break compatibility with existing applications.
Backporting Solution: The administrative team applies a backported security patch from the latest OpenSSL version while keeping the same CentOS 7 OpenSSL package version to maintain compatibility.
2. Maintaining Stability in Enterprise Software
Scenario: A financial institution relies on a custom-built web application that runs on an older version of Java (JDK 8). Upgrading to JDK 17 would require significant code refactoring, delaying business operations.
Backporting Solution: The organization applies specific JDK 17 security fixes to JDK 8, ensuring critical vulnerabilities are patched while avoiding a full upgrade.
Difficulties with ‘Backporting’ in Cyber Security
Backporting is often used as a temporary solution to maintain security in legacy systems, but it introduces significant risks and challenges from a cybersecurity standpoint. Backporting often creates issues for cyber security teams such as tracking, residual risk, delays in response to emerging threats, and additional difficulties with it comes to audit and compliance complications.
1. Incomplete Security Fixes & Residual Vulnerabilities
Backported patches may fix specific vulnerabilities but often lack broader security improvements from newer software versions. Systems may remain vulnerable to related exploits or attacks that the newer version fully mitigates.
Example: A backported OpenSSL patch may fix a buffer overflow issue, but newer versions include hardened memory protections that aren’t included in the backport, leaving the system partially vulnerable.
2. Delayed Response to Emerging Threats
Adapting and testing security patches for older versions takes time, leading to delayed deployments. Along with organizations remain exposed to zero-day vulnerabilities for longer periods increasing risk. It is recommended that organizations develop a patching policy that prioritizes official updates over backporting whenever possible.
Example: A new RCE (Remote Code Execution) vulnerability is discovered in Apache 2.4.58. However, the organization runs Apache 2.4.29 and needs to backport the fix. The process of backporting takes weeks or months, increasing the attack window for adversaries.
3. Security Compliance & Audit Challenges
Many security frameworks (e.g., PCI-DSS, NIST, ISO 27001, NIS2, GDPR) require the use of vendor-supported software and timely patching. Backporting complicates compliance verification. Security scanners detect outdated software versions and report vulnerabilities that are technically a false positive. This is due to vulnerability scanning does execute architectural review of components of a system targeted for vulnerability assessment. Backporting can often lead to auditors rejecting backported patches unless extensive documentation is provided.
This is especially true when doing regular required PCI-DSS ASV assessments using scanning systems as required by PCI-DSS. This is due to rigorous requirements for specific ‘scanning’ methods and findings doctrine for PCI ASVs.
Example: A company running PHP 7.4 with backported security fixes fails a PCI-DSS scan because the scanner flags PHP 7.4 as vulnerable. The company must manually justify that fixes were applied, delaying compliance approval. Simply stating that a service has been patched will generally not be enough of a justification when it comes to PCI-DSS, and others compliance frameworks (GDPR, ISO, NIS2) without the specific security patch reference. There will be many different patches released for outdated versions of software, each one to fix a specific vulnerability or group of vulnerabilities.
Again, it is recommended that organizations develop a patching policy that prioritizes official updates over backporting whenever possible. While also maintain detailed patching documentation and work with compliance auditors to validate backported fixes.
4. Increased Attack Surface Due to Dependency Issues
Security patches are designed for modern system architectures, dependencies, and libraries. Backporting may create compatibility issues that introduce new security risks. A patched application may still be vulnerable due to outdated dependencies that lack the latest security protections.
Example: A Node.js application runs on an outdated Express.js framework with backported security fixes. However, the backport does not address critical dependency vulnerabilities in other libraries, leaving the system exposed.
Security teams should work closely with application and system owners to understand what is covered in a specific backport solution and what residual risk is present thus considering additional controls to mitigate the residual risk. Senior security staff would then need to adjust their Business Impact Analysis (BIA) and Risk Assessment (RA) accordingly to account for the residual risk to the organization.
5. Backported Patches Are Not Officially Supported
When backporting vulnerabilities, vendors do not officially support backported patching, meaning organizations must rely on in-house security teams or third parties to maintain them. If a backported patch introduces bugs or breaks functionality, there is no official vendor support to resolve issues. Even with long-term support (LTS) contract, backporting is not covered and often would need additional internal resources to support end-of-life (EOL) systems and components, or third-party contracts.
Example: A company backports a security patch to an end-of-life Linux distribution (e.g., Ubuntu16.04). A critical bug emerges after patching, but the vendor no longer provides updates, forcing the company to manage fixes themselves. Thus, opening up delays in security critical business systems, creating additional residual risk, audit and compliance complications, and additional operational overhead to cyber-security teams.
6. Increased Complexity & Maintenance Overhead
Backporting creates technical debt, making long-term security management more complex and expensive. Security teams must manually track which patches have been applied and ensure they remain effective over time. This creates additional issues like future updates becoming harder, increasing the risk of misconfigurations and security gaps.
Example: An organization running an ERP system on Java 8 continuously backports security fixes instead of upgrading. Over time, maintaining the patches becomes costly, and the system remains vulnerable to modern attack techniques.
Establish a clear policy for when to backport and when to upgrade, ensuring long-term security. Backporting should only be considered a short-term mitigation and never a long-term fix. Application teams, system owners, system administrators, and leadership should understand the goals of the cyber security program and if additional resources are needed, routine BIAs and RAs would help to establish strategies to solve long-term backporting.
7. Exposure to Supply Chain Attacks
With the complexities of business technologies and engagements today, organizations may rely on third-party or unofficial sources for backported patches, increasing the risk of supply chain attacks.
Example: A backported patch for an outdated WordPress plugin is downloaded from an untrusted third-party repository. The patch contains malicious code, allowing attackers to inject malware or ransomware into the system.
Though many organizations have talented development and admin teams, the speed at which business moves and expands today is hard for organization’s teams to keep up. More reliance on third-party resources for backporting security flaws in systems, applications, and components is ever more prevalent. Therefore, only use trusted sources for security patches and verify patch integrity before deployment. However, even trusted sources may also have compromised solutions, it is best to remain in an N-1 or up-to-date state wherever possible.
Final Thoughts
Backporting is a temporary risk management strategy but should not replace full software upgrades. Organizations must minimize reliance on backporting and prioritize officially supported versions to maintain a strong cybersecurity posture and reduce risk.
Many developers and system administrators have varying levels of risk awareness, often prioritizing deadlines, functionality, and performance over security. As a result, security is frequently treated as a secondary concern. To mitigate this, security must be integrated into the Software Development Lifecycle (SDLC) from the outset, following a DevSecOps approach that ensures security is considered alongside functionality and performance.
Developing and maintaining secure, updated solutions for complex systems is challenging. However, security is not just an IT issue, it must be a companywide priority. A shared understanding of risk across all teams is essential for leadership to accurately assess the organization’s security posture, staff limitations, and available resources (FTEs). Aligning security priorities with policy, compliance, and business objectives enables organizations to effectively manage risk, meet regulatory requirements, and achieve long-term security goals.
Recent Case Studies and Research
Identifying specific cybersecurity incidents directly attributed to backporting vulnerabilities is challenging, as organizations often do not disclose detailed internal patch management practices. However, several studies and reports highlight the potential risks associated with backporting:
Increased Attack Surface Due to Dependency Issues
Case Study: National Public Data Breach (April 2024)
In April 2024, National Public Data (NPD), a company providing background checks, was breached through a third-party contractor who failed to update their security patches. This oversight allowed attackers to steal sensitive personal data, including Social Security numbers and addresses, affecting approximately 2.9 billion individuals.
National Public Data Breach (April 2024) – Possibly Related to Backporting
Cause: Third-party contractor failed to apply security patches.
Connection to Backporting:
- The breach was due to outdated security patches on a third-party system.
- If the contractor had been using an older system with backported patches, this could have contributed to vulnerabilities.
Sources: https://fortifydata.com/blog/third-party-data-breaches-of-2024/?utm_source=chatgpt.com
Delayed Response to Emerging Threats
Case Study: Equifax Data Breach (2017)
In 2017, Equifax suffered a significant data breach when attackers exploited an unpatched vulnerability in the Apache Struts framework. Despite the availability of a patch, delays in its application allowed attackers to access sensitive information of approximately 150 million customers.
Equifax Data Breach (2017) – Possibly Related to Backporting
Cause: Unpatched Apache Struts vulnerability (CVE-2017-5638).
Connection to Backporting:
- Equifax failed to apply an official patch in time, but there is no direct mention of backporting.
- If Equifax had been running an older version of Apache Struts with backported patches instead of upgrading, this could have contributed to the problem.
1. Backporting Vulnerabilities in Web Applications:
Study: Research presented at the USENIX Security Symposium examined the challenges of backporting security patches in web applications, particularly focusing on injection vulnerabilities. The study highlighted that improper backporting could introduce new vulnerabilities or fail to fully address existing ones, emphasizing the need for careful analysis and testing during the backporting process.
2. Backporting Practices in Package Dependency Networks:
Study: An analysis of backporting practices in package dependency networks, published in the IEEE Transactions on Software Engineering, explored how backporting aims to bring bug or vulnerability fixes from newer to older software releases. The study found that while backporting is beneficial for maintaining legacy systems, it requires extensive technical expertise and can introduce new risks if not properly managed.
3. Challenges in Backporting Security Fixes:
Report: A report by SentinelOne discussed the complexities of backporting, noting that adapting security patches designed for modern systems to older versions can result in unanticipated side effects. The report emphasized that backporting requires extensive technical expertise and may introduce new risks if not properly tested.
1. Shi, Z., Luo, L., & Zhang, D. (2022). Challenges in backporting security patches for web applications. Presented at the USENIX Security Symposium. Retrieved from https://www.usenix.org/conference/usenixsecurity22/presentation/shi
2. Decan, A., Mens, T., & Gonzalez-Barahona, J. M. (2021). Backporting practices in package dependency networks. IEEE Transactions on Software Engineering. Retrieved from https://decan.lexpage.net/files/TSE-2021.pdf
3. SentinelOne. (n.d.). Challenges in backporting security fixes. SentinelOne Cybersecurity Reports. Retrieved from https://www.sentinelone.com/cybersecurity-101/cybersecurity/backporting/
