CVE-2026-22697 is a heap-based buffer overflow vulnerability identified in NASA's CryptoLib, a software-only implementation of the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP). CryptoLib is used to secure communications between spacecraft running the core Flight System (cFS) and ground stations. The vulnerability exists in versions prior to 1.4.3 within the KMC crypto service integration. Specifically, when decoding Base64-encoded ciphertext or cleartext fields returned by the KMC service, the destination buffer is allocated based on an expected output length (len_data_out). However, the Base64 decoder writes output based on the actual input length without enforcing a limit on the destination buffer size. This discrepancy allows an attacker to craft an oversized Base64 string in the KMC JSON response, causing out-of-bounds writes on the heap. The consequences include process crashes (denial of service) and potentially remote code execution under certain conditions. The vulnerability does not require authentication or user interaction and can be exploited remotely over the network. Although no known exploits are reported in the wild, the vulnerability's CVSS score of 7.5 (high) reflects its significant impact on availability and the ease of exploitation. The flaw was patched in CryptoLib version 1.4.3 by correcting buffer size handling during Base64 decoding. This vulnerability is classified under CWE-122 (Heap-based Buffer Overflow), a common and dangerous software weakness that can lead to severe security breaches if exploited.

For European organizations, especially those involved in aerospace, satellite communications, and space research, this vulnerability poses a critical risk. The affected CryptoLib is integral to securing spacecraft-to-ground communications, meaning exploitation could disrupt mission-critical data exchanges, leading to loss of availability and potential compromise of operational integrity. Although confidentiality and integrity impacts are not directly indicated, the possibility of remote code execution could allow attackers to escalate privileges or manipulate communications. Disruptions could affect satellite control, telemetry, and command functions, with cascading effects on dependent infrastructure and services. Given Europe's active participation in space programs (e.g., ESA member states) and aerospace industries, the vulnerability could impact national security, scientific missions, and commercial satellite operations. The lack of known exploits suggests a window for proactive mitigation, but the ease of exploitation and network accessibility heighten urgency. Organizations failing to patch may face denial of service or unauthorized code execution, potentially leading to mission failures or data manipulation.

The primary mitigation is to upgrade CryptoLib to version 1.4.3 or later, where the heap buffer overflow has been patched. Organizations should audit their use of CryptoLib and related components to identify affected versions. Additionally, implement strict input validation on Base64-encoded data received from the KMC service, ensuring that input lengths do not exceed expected bounds before decoding. Employ runtime protections such as heap canaries, address space layout randomization (ASLR), and control flow integrity (CFI) to reduce exploitation risk. Conduct thorough code reviews and fuzz testing on cryptographic service integrations to detect similar buffer handling issues. Network segmentation and strict access controls can limit exposure of vulnerable services. Monitoring for anomalous KMC JSON responses or unexpected process crashes can provide early detection of exploitation attempts. Finally, coordinate with space communication partners to ensure consistent patch deployment and secure protocol implementations.