Introduction
The US Cybersecurity and Infrastructure Security Agency (CISA) and the Federal Bureau of Investigation (FBI) have issued a Secure by Design Alert [7], highlighting the critical issue of buffer overflow vulnerabilities in software development. These vulnerabilities pose significant security risks and are frequently exploited by cyber actors, necessitating a shift towards secure coding practices and the adoption of memory-safe programming languages.
Description
A new Secure by Design Alert from the US Cybersecurity and Infrastructure Security Agency (CISA) and the Federal Bureau of Investigation (FBI) warns software developers against creating code with buffer overflow vulnerabilities, labeling them as “unforgivable defects.” These prevalent flaws in memory-unsafe software design can lead to severe security issues, including complete system compromise [4] [6], data corruption [2] [5] [7] [8] [11] [12] [13], unauthorized code execution [5] [7] [8] [12] [13], and network breaches, making them frequent targets for cyber actors [13]. Threat actors [5] [7] [8] [12], including those from China, often exploit these vulnerabilities to gain initial access to networks and move laterally within them [5] [12], using them as entry points for broader attacks [8]. Notably, these vulnerabilities have been identified in products from major vendors, including Microsoft [4], Ivanti [1] [2] [4] [6] [9], and VMware vCenter [1] [2] [9], with specific flaws such as CVE-2025-21333 and CVE-2024-49138 in Microsoft products, the latter being exploited in zero-day attacks and rated 7.8/10 on the CVSS scale [4]. A critical VMware vCenter flaw (CVE-2024-38812) required a second patch after the initial fix was inadequate [4], and Ivanti’s Connect Secure had a stack-based buffer overflow vulnerability (CVE-2025-0282) that was also exploited in zero-day attacks, rated 9/10 on the CVSS scale [4]. Additionally, the advisory references CVE-2023-6549, a vulnerability in Citrix Netscaler ADC and Netscaler Gateway [2], underscoring the urgent need for improved cybersecurity measures.
The advisory emphasizes that unsafe software development practices [4] [6] [9], particularly the use of memory-unsafe programming languages like C and C++ [4] [6] [9], pose significant risks to national and economic security [1] [4] [6] [9]. Buffer overflow vulnerabilities arise when a program reads or writes memory beyond its allocated boundaries due to improper memory initialization [4] [6]. Despite the availability of effective mitigations [10], many manufacturers continue to employ these unsafe practices [10], allowing buffer overflow vulnerabilities to persist [2] [10]. While the adoption of memory-safe programming languages [2] [8] [13], such as Rust [4] [7] [8], Go [1] [4] [9] [11], Swift [1] [4] [9], and Python [4], is encouraged for new code, the advisory acknowledges that addressing memory safety vulnerabilities is complex and requires substantial effort [4]. Other mitigations may only address specific issues [4], and despite the availability of well-documented fixes [4], these vulnerabilities remain prevalent [2] [3] [4] [5] [6] [7] [8] [9] [12] [13]. To mitigate these risks [1] [9] [13], software development firms are recommended to utilize safe and modern programming practices [1] [9], including compiler flags [9], unit tests with AddressSanitizer and MemorySanitizer [1] [9], static analysis [1] [8] [9], manual evaluations [1] [9], fuzzing [1] [8] [9], and reviewing previously identified software issues [1] [9].
To combat these threats [11], CISA advocates for a “secure by design” approach in software development [11], which prioritizes security from the outset rather than as an afterthought [11]. The Alert outlines effective techniques grounded in secure design principles and best practices, encouraging the implementation of compiler protections like runtime checks and canaries [8]. Manufacturers are urged to transition legacy code to memory-safe alternatives and conduct thorough adversarial testing. Additionally, CISA and the FBI stress the importance of creating a memory-safety roadmap for future product development. Software customers are also encouraged to demand secure products by requesting a software bill of materials and secure software development attestations.
Saeed Abbasi [7] [8], manager of vulnerability research at Qualys Threat Research Unit (TRU) [7] [8], underscores the urgent need to eliminate unsafe practices [8], asserting that the world must achieve zero tolerance for memory-unsafe code by 2025 [8]. He acknowledges the challenges of rewriting old systems but emphasizes that allowing attackers to exploit buffer overflows is far more detrimental, framing these vulnerabilities as failures of priorities rather than inevitabilities [7] [8]. Abbasi advocates for phased transitions to memory-safe programming options and public commitments to a secure-by-design roadmap [7]. The advisory highlights critical buffer overflow vulnerabilities affecting major vendors, including Microsoft [4], VMware [1] [2] [4] [6] [9], and Ivanti [2] [4] [6], with notable flaws such as CVE-2025-21333 and CVE-2024-49138 in Microsoft products, the latter being exploited in zero-day attacks and rated 7.8/10 on the CVSS scale [4]. A critical VMware vCenter flaw (CVE-2024-38812) required a second patch after the initial fix was inadequate [4], and Ivanti’s Connect Secure had a stack-based buffer overflow vulnerability (CVE-2025-0282) that was also exploited in zero-day attacks, rated 9/10 on the CVSS scale [4]. Additionally, the advisory references CVE-2023-6549, a vulnerability in Citrix Netscaler ADC and Netscaler Gateway [2], as part of its emphasis on the need for improved cybersecurity measures.
Further information on enterprise software products and services can be found on CISA’s Secure by Design Pledge page [5], a voluntary initiative that encourages enterprises to prioritize security in their software products and services [7], including cloud-based solutions and Software as a Service (SaaS) [7]. This initiative aims to promote industry-wide improvements in cybersecurity by encouraging manufacturers to adopt secure development practices and eliminate buffer overflow vulnerabilities in their products.
Conclusion
The Secure by Design Alert from CISA and the FBI underscores the critical need for the software industry to prioritize security in development processes. By transitioning to memory-safe programming languages and adopting secure coding practices, developers [1] [2] [3] [4] [6] [7] [9] [10] [11] [13] can mitigate the risks associated with buffer overflow vulnerabilities. The call to action is clear: eliminate unsafe practices and commit to a secure-by-design approach to protect national and economic security. As the industry moves towards these goals, the collaboration between manufacturers, developers, and consumers will be essential in achieving a more secure digital landscape.
References
[1] https://www.msspalert.com/brief/buffer-overflow-vulnerability-elimination-in-software-sought-by-feds
[2] https://www.cybersecuritydive.com/news/fbi-cisa–hackers-buffer-overflow/740072/
[3] https://executivegov.com/2025/02/cisa-fbi-alert-buffer-overflow-vulnerability/
[4] https://www.csoonline.com/article/3823937/cisa-fbi-call-software-with-buffer-overflow-issues-unforgivable.html
[5] https://www.manufacturing.net/cybersecurity/news/22933323/cisa-fbi-warn-of-buffer-overflow-vulnerabilities
[6] https://soc-news.com/fbi-cisa-buffer-overflow-warning/
[7] https://informationsecuritybuzz.com/cisa-fbi-warn-exploiti-buffer-overflow/
[8] https://www.infosecurity-magazine.com/news/cisa-fbi-buffer-overflow/
[9] https://www.channele2e.com/brief/feds-want-to-eliminate-buffer-overflow-vulns
[10] https://insidecybersecurity.com/daily-news/cisa-fbi-publish-secure-design-alert-memory-safety-offering-steps-boost-product-security
[11] https://www.techspot.com/news/106770-us-cyber-defense-agency-urges-developers-eliminate-buffer.html
[12] https://www.cisa.gov/news-events/alerts/2025/02/12/cisa-and-fbi-warn-malicious-cyber-actors-using-buffer-overflow-vulnerabilities-compromise-software
[13] https://24x7mag.com/medical-equipment/software/cybersecurity-software/cisa-fbi-urge-action-buffer-overflow-threats-new-security-alert/
