In June 2025, the Cybersecurity and Infrastructure Security Agency (CISA) and the National Security Agency (NSA) jointly released a comprehensive guide titled Memory Safe Languages: Reducing Vulnerabilities in Modern Software Development. This document addresses the persistent issue of memory safety vulnerabilities, which have long plagued software systems and led to significant security breaches.
Understanding Memory Safety Vulnerabilities
Memory safety vulnerabilities occur when programming languages allow unintended access, allocation, or deallocation of memory. These flaws can be exploited by malicious actors to access sensitive data, corrupt information, or execute arbitrary code. Notable incidents such as the Heartbleed and BadAlloc vulnerabilities have underscored the severe consequences of these issues, affecting millions of devices and compromising critical infrastructure.
The Prevalence of Memory Safety Issues
Analyses have shown that a significant proportion of software vulnerabilities stem from memory safety issues. For instance, a 2019 study revealed that 66% of Common Vulnerabilities and Exposures (CVEs) for iOS 12 and 71% for macOS Mojave were related to memory safety problems. Furthermore, Google’s Project Zero found that 75% of CVEs exploited in real-world attacks were memory safety vulnerabilities, with 67% of zero-day vulnerabilities discovered in 2021 falling into this category.
Transitioning to Memory-Safe Languages
To mitigate these risks, CISA and the NSA advocate for the adoption of memory-safe programming languages (MSLs). Unlike traditional languages that require manual memory management, MSLs incorporate safety mechanisms that prevent common memory-related errors. Languages such as Rust, Go, and Swift are designed to handle memory allocation and deallocation automatically, reducing the likelihood of vulnerabilities.
Case Study: Android’s Shift to Memory Safety
The guide highlights Android’s transition to memory-safe languages as a successful example. In 2019, memory safety issues accounted for 76% of all Android vulnerabilities. By prioritizing MSLs like Rust and Java for new development, Android reduced memory safety vulnerabilities to 24% by 2024, demonstrating the effectiveness of this approach.
Implementing Memory Safety Mechanisms
The guide outlines key safety features inherent in MSLs:
– Automatic Memory Management: MSLs handle memory allocation and deallocation, preventing issues like buffer overflows and use-after-free errors.
– Strict Type Systems: These languages enforce type safety, reducing the risk of type-related errors that can lead to security vulnerabilities.
– Immutable Data Structures: By default, data structures are immutable, preventing unintended modifications and enhancing security.
Challenges and Considerations
Transitioning to MSLs presents challenges, including the need for developer training, potential performance trade-offs, and the complexity of integrating new languages into existing codebases. However, the long-term benefits, such as enhanced security and reduced vulnerability management costs, outweigh these initial hurdles.
Developing a Memory Safety Roadmap
CISA and the NSA recommend that software manufacturers create and publish memory safety roadmaps. These roadmaps should detail plans for adopting MSLs, timelines for transitioning existing codebases, and strategies for training development teams. By doing so, organizations demonstrate a commitment to secure-by-design principles and proactive vulnerability mitigation.
Conclusion
The joint guidance from CISA and the NSA marks a significant step toward enhancing software security through the adoption of memory-safe programming practices. By transitioning to MSLs and developing comprehensive memory safety roadmaps, software manufacturers can significantly reduce the prevalence of memory safety vulnerabilities, leading to more secure and reliable software systems.
