CVE-2024-22087 is a critical security vulnerability identified in the Pico HTTP Server, specifically in the 'route' function within the main.c source file. The vulnerability arises from the use of the unsafe 'sprintf' function to handle URI input, which leads to a stack-based buffer overflow when processing an excessively long URI. This buffer overflow (classified under CWE-787: Out-of-bounds Write) enables an attacker to overwrite the stack memory, potentially allowing remote code execution (RCE) without requiring any authentication or user interaction. The vulnerability has a CVSS v3.1 base score of 9.8, indicating its critical severity, with attack vector being network-based (AV:N), no privileges required (PR:N), no user interaction (UI:N), and impacts confidentiality, integrity, and availability (C:H/I:H/A:H). Exploiting this flaw would allow an attacker to execute arbitrary code on the affected server, potentially taking full control over the system running the Pico HTTP Server. The vulnerability is present in an unspecified version of the Pico HTTP Server, and no patches or vendor advisories are currently available. Although no known exploits are reported in the wild yet, the ease of exploitation and the severity of impact make this a high-risk issue that demands immediate attention from users of this software.

For European organizations, the impact of this vulnerability could be significant, especially for those relying on the Pico HTTP Server in their infrastructure. Successful exploitation could lead to full system compromise, data breaches, service disruption, and lateral movement within internal networks. This could affect confidentiality of sensitive data, integrity of critical systems, and availability of web services. Given the critical nature of the vulnerability and the lack of authentication or user interaction requirements, attackers could remotely exploit vulnerable servers at scale. Organizations in sectors such as finance, healthcare, government, and critical infrastructure, which often have stringent data protection and service availability requirements under regulations like GDPR and NIS Directive, could face severe operational and compliance consequences. Additionally, the potential for remote code execution could facilitate ransomware deployment or espionage activities targeting European entities.

Immediate mitigation steps include: 1) Identifying and inventorying all instances of Pico HTTP Server within the organization’s environment. 2) Applying any available patches or updates from the vendor as soon as they are released. Since no patches are currently available, organizations should consider temporary workarounds such as implementing Web Application Firewalls (WAFs) with rules to detect and block unusually long URIs or suspicious HTTP requests targeting the vulnerable endpoint. 3) Employ network-level protections by restricting access to the Pico HTTP Server to trusted networks or VPNs where possible. 4) Conduct thorough monitoring and logging of HTTP requests to detect potential exploitation attempts. 5) Employ intrusion detection/prevention systems (IDS/IPS) tuned to detect buffer overflow attack patterns. 6) Consider isolating or decommissioning Pico HTTP Server instances if they are not critical or can be replaced with more secure alternatives. 7) Educate security teams about this vulnerability to ensure rapid response to any suspicious activity. 8) Prepare incident response plans to quickly contain and remediate any exploitation attempts.