CVE-2025-54878: NASA CryptoLib Buffer Overflow Vulnerability

CVE-2025-54878 Overview

CVE-2025-54878 is a heap buffer overflow vulnerability in NASA CryptoLib version 1.4.0 and earlier. CryptoLib 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 flaw resides in the Initialization Vector (IV) setup logic for telecommand (TC) frames, where missing bounds checks allow a single-byte write past the end of a freshly allocated heap buffer. An attacker submitting a crafted telecommand frame can corrupt heap memory, producing crashes or potentially more severe exploitation outcomes.

Critical Impact

A malformed telecommand frame can corrupt the heap, resulting in denial of service of spacecraft-to-ground cryptographic processing or undefined behavior that may extend to memory corruption exploitation.

Affected Products

• NASA CryptoLib version 1.4.0
• NASA CryptoLib versions prior to 1.4.0
• Spacecraft and ground station deployments using CryptoLib for SDLS-EP

Discovery Timeline

• 2025-08-11 - CVE-2025-54878 published to NVD
• 2025-08-27 - Last updated in NVD database

Technical Details for CVE-2025-54878

Vulnerability Analysis

The vulnerability is classified as a heap-based buffer overflow [CWE-122]. CryptoLib processes telecommand frames as part of the CCSDS SDLS-EP protocol, which provides authenticated and encrypted command uplinks to spacecraft. During IV setup for an incoming TC frame, the library allocates a heap buffer sized to the expected IV length, then copies attacker-controlled IV bytes from the frame into that buffer.

Because the copy logic does not validate that the source length matches the destination buffer size, a crafted frame can trigger a one-byte write beyond the allocated region. This off-by-one overflow corrupts adjacent heap metadata or neighboring chunks. The protocol context exposes this code path to network-reachable telecommand traffic, which raises the attack surface beyond locally crafted inputs.

Root Cause

The root cause is missing bounds enforcement in the IV copy operation within the TC frame IV setup routine. The code trusts a length value derived from the inbound frame without comparing it against the size of the destination heap allocation. Refer to the NASA CryptoLib commit 9b5b294 for the corrective patch.

Attack Vector

Exploitation requires no authentication and no user interaction. An attacker capable of delivering a telecommand frame to a system running CryptoLib can supply a malformed IV field that overruns the heap buffer by one byte. The most reliable outcome is a process crash and denial of service for cryptographic frame processing. Heap corruption may also enable further memory manipulation depending on allocator state and adjacent objects.

The vulnerability is described in the GitHub Security Advisory GHSA-9qph-pxfm-q9g4. No public proof-of-concept exploit is currently available.

Detection Methods for CVE-2025-54878

Indicators of Compromise

• Unexpected crashes or aborts in processes linking against libcryptolib during telecommand frame processing
• Heap corruption signatures in core dumps referencing the TC frame IV setup code path
• Anomalous telecommand frames with malformed or oversized IV fields reaching ground station or spacecraft simulator endpoints

Detection Strategies

• Deploy AddressSanitizer (ASan) or similar heap instrumentation in test and staging environments to catch the off-by-one write before production deployment
• Inventory all binaries linked against NASA CryptoLib and verify the linked version against the patched release
• Monitor for repeated abnormal termination of CryptoLib-dependent services, which may indicate exploitation attempts

Monitoring Recommendations

• Enable verbose protocol logging on telecommand ingress paths to capture frame structure metadata for forensic review
• Alert on process restarts or crash loops of ground segment services that integrate CryptoLib
• Correlate network telemetry for unauthorized or anomalous telecommand traffic sources against expected ground station peers

How to Mitigate CVE-2025-54878

Immediate Actions Required

• Upgrade NASA CryptoLib to the patched release that contains commit 9b5b294
• Rebuild and redeploy all dependent ground station, spacecraft simulator, and flight software components that statically or dynamically link CryptoLib
• Restrict telecommand ingress to authenticated and authorized ground station peers using network-layer controls

Patch Information

The advisory states the issue has been patched. Apply the fix referenced in the NASA CryptoLib GitHub repository and review the GHSA-9qph-pxfm-q9g4 advisory for full remediation guidance. Operators should validate the upgrade in a representative test environment before deploying to mission-critical systems.

Workarounds

• Filter inbound telecommand frames at the network boundary to reject frames with IV fields that do not match the expected protocol size
• Run CryptoLib-dependent processes with hardened allocator settings and exploit mitigations such as heap canaries and ASLR enabled
• Isolate telecommand processing services in restricted execution environments to limit blast radius if corruption occurs

# Configuration example: pin CryptoLib to the patched commit during build
git clone https://github.com/nasa/CryptoLib.git
cd CryptoLib
git checkout 9b5b294ec09da450d2d4d05aea2db604ead48be1
mkdir build && cd build
cmake ..
make