CVE-2026-22026 is a vulnerability identified in NASA's CryptoLib, a software library implementing the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between spacecraft running the core Flight System (cFS) and ground stations. The flaw exists in versions prior to 1.4.3 within the libcurl write_callback function used by the Key Management Client (KMC) crypto service. Specifically, the client reallocates response buffers without imposing any size limits or performing overflow checks. This allows a malicious KMC server to send arbitrarily large HTTP responses, forcing the client to allocate excessive amounts of memory. The uncontrolled memory growth can exhaust system resources, causing the process to be terminated by the operating system, resulting in a denial of service (DoS). The vulnerability does not require authentication or user interaction and can be exploited remotely over the network. Although no known exploits are currently in the wild, the issue has been addressed in CryptoLib version 1.4.3 by adding appropriate limits and checks on buffer sizes during reallocation. The vulnerability is classified under CWE-789 (Memory Allocation with Excessive Size Value) and has a CVSS 4.0 base score of 8.2, indicating high severity due to its potential to disrupt availability and ease of exploitation.

For European organizations, particularly those involved in aerospace, satellite communications, and space research, this vulnerability poses a significant risk of denial of service. Exploitation could disrupt critical communication links between spacecraft and ground stations, potentially impacting mission operations, data integrity, and command/control capabilities. The unbounded memory allocation can lead to system crashes or forced process termination, causing service outages. Given the specialized nature of CryptoLib and its use in space-related applications, affected organizations may face operational delays, increased recovery costs, and potential safety risks if spacecraft communications are interrupted. Additionally, organizations relying on this library for secure communications may experience degraded trust in their security posture. The lack of known exploits currently reduces immediate risk, but the vulnerability’s ease of exploitation and high impact warrant urgent remediation to prevent future attacks.

The primary mitigation is to upgrade all instances of NASA CryptoLib to version 1.4.3 or later, where the vulnerability has been patched. Organizations should audit their environments to identify any deployments of CryptoLib versions prior to 1.4.3, especially within KMC crypto service clients. Implement strict input validation and size limits on HTTP response buffers to prevent unbounded memory allocation. Network-level controls such as firewall rules and intrusion detection systems should monitor and restrict communications with untrusted or unknown KMC servers. Employ runtime memory monitoring and process watchdogs to detect and recover from abnormal memory usage patterns. Additionally, organizations should engage with NASA or relevant vendors for any further security advisories or patches. Regularly updating and testing incident response plans to handle potential denial of service scenarios related to this vulnerability is also recommended.