CVE-2026-22027 is a heap-based buffer overflow vulnerability identified in NASA's CryptoLib software, which implements 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 vulnerability resides in the convert_hexstring_to_byte_array() function within the MariaDB SA interface of CryptoLib versions prior to 1.4.3. This function decodes hex strings from the database (such as IV, ARSN, ABM fields) and writes the resulting bytes into a buffer provided by the caller without verifying the buffer's capacity. If a malformed or oversized hex string is present in the database, this unchecked write can overflow the heap buffer, leading to corruption of adjacent heap memory. Such memory corruption can cause unpredictable behavior including crashes or potential exploitation for code execution, although no public exploits are currently known. The vulnerability requires high privileges to exploit, as it involves importing data from the database, and does not require user interaction or network access, limiting remote exploitation. The issue has been addressed in CryptoLib version 1.4.3 by adding proper bounds checking to prevent buffer overflow. Given CryptoLib's role in securing spacecraft communications, this vulnerability poses risks to the confidentiality, integrity, and availability of critical space mission data if exploited.

For European organizations involved in aerospace, satellite communications, or space research that utilize NASA's CryptoLib, this vulnerability could have significant operational impacts. Exploitation could lead to heap memory corruption causing denial of service conditions or potentially enabling attackers with high privileges to execute arbitrary code or manipulate sensitive cryptographic parameters. This threatens the confidentiality and integrity of spacecraft-to-ground communications, which are critical for mission control and data integrity. Disruption or compromise of these communications could impact satellite operations, scientific data collection, or national security-related space assets. Although the vulnerability requires local high privileges and is not remotely exploitable, insider threats or compromised systems could leverage this flaw. The absence of known exploits reduces immediate risk, but the critical nature of affected systems demands prompt remediation to avoid potential mission degradation or data breaches.

European organizations should immediately upgrade NASA CryptoLib to version 1.4.3 or later, where the vulnerability is patched with proper buffer capacity checks. Additionally, implement strict access controls and auditing on systems managing the MariaDB databases containing SA fields to prevent unauthorized modification of hex strings. Regularly validate and sanitize all database inputs to detect malformed or oversized hex strings that could trigger overflows. Employ runtime memory protection mechanisms such as heap canaries and address space layout randomization (ASLR) on systems running CryptoLib to mitigate exploitation impact. Conduct thorough code reviews and fuzz testing on components handling external data inputs to identify similar vulnerabilities proactively. Finally, establish monitoring for anomalous application crashes or memory corruption events that could indicate exploitation attempts.