CVE-2025-64096 is a stack-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). This library secures communication between spacecraft running the core Flight System (cFS) and ground stations. The vulnerability resides in the Crypto_Key_update() function within crypto_key_mgmt.c, where the function processes TLV (Type-Length-Value) packets containing a length field (pdu_len) that is attacker-controlled. Prior to version 1.4.2, the code does not properly validate this length against the size of a static array (kblk[98]). If an attacker supplies a spoofed TLV packet with an excessive length, the function calculates a number of keys that exceeds the array bounds, causing a stack buffer overflow. This overflow can corrupt adjacent memory on the stack, potentially allowing an attacker to execute arbitrary code, crash the system, or manipulate sensitive data. The vulnerability requires only low privileges (PR:L) and no user interaction (UI:N), and can be exploited remotely over the network (AV:N). The scope is unchanged (S:U), meaning the impact is confined to the vulnerable component. The CVSS v3.0 score of 8.8 reflects high impact on confidentiality, integrity, and availability. No public exploits are currently known, but the vulnerability is critical given the sensitive nature of space communication systems. The issue was addressed in CryptoLib version 1.4.2 by adding proper bounds checking to prevent out-of-bounds writes.

The impact of CVE-2025-64096 on European organizations is significant, especially for those involved in aerospace, satellite communications, and space research. The vulnerability compromises the security of communications between spacecraft and ground stations, potentially allowing attackers to intercept, alter, or disrupt critical data transmissions. This could lead to loss of mission data, unauthorized command injection, or denial of service affecting spacecraft operations. European space agencies such as ESA and companies providing satellite services or ground station infrastructure could face operational disruptions and data breaches. The confidentiality of sensitive telemetry and command data is at risk, as is the integrity and availability of space communication links. Given the critical role of space assets in telecommunications, navigation, and defense, exploitation could have cascading effects on national security and commercial services. The remote exploitability and lack of required user interaction increase the threat level. Although no known exploits exist yet, the vulnerability's presence in widely used space communication software demands urgent attention to prevent potential future attacks.

To mitigate CVE-2025-64096, affected organizations must upgrade CryptoLib to version 1.4.2 or later, which includes the necessary bounds checking to prevent buffer overflows. Where immediate upgrade is not feasible, organizations should implement strict network segmentation to isolate spacecraft communication systems from untrusted networks, reducing exposure to remote attacks. Deploy deep packet inspection and anomaly detection systems to monitor for malformed TLV packets with suspicious length fields indicative of exploitation attempts. Employ rigorous input validation at all protocol layers to reject packets with invalid or out-of-range length values. Conduct regular security audits and code reviews of custom or integrated cryptographic libraries to detect similar vulnerabilities. Additionally, implement runtime protections such as stack canaries, address space layout randomization (ASLR), and control flow integrity (CFI) in the software environment to mitigate exploitation impact. Establish incident response plans specific to space communication systems to quickly address potential compromises. Collaboration with NASA and other space agencies for threat intelligence sharing is recommended to stay informed of emerging exploits or patches.