CVE-2025-29910: NASA CryptoLib DoS Vulnerability

CVE-2025-29910 Overview

CVE-2025-29910 is a memory leak vulnerability discovered in NASA's CryptoLib, a software-only solution using 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 was identified in the crypto_handle_incrementing_nontransmitted_counter function, where memory allocated using malloc is not always properly freed, leading to resource exhaustion over time.

Critical Impact

Systems using CryptoLib for high-throughput or continuous data streams face potential Denial of Service (DoS) conditions due to gradual memory exhaustion, particularly impacting long-running spacecraft communication processes.

Affected Products

• NASA CryptoLib versions 1.3.3 and prior
• Systems using CryptoLib for spacecraft-to-ground station communications
• Any implementation handling high-throughput or continuous data streams via CryptoLib

Discovery Timeline

• 2025-03-17 - CVE-2025-29910 published to NVD
• 2025-04-30 - Last updated in NVD database

Technical Details for CVE-2025-29910

Vulnerability Analysis

This vulnerability represents a classic memory management flaw (CWE-401: Missing Release of Memory after Effective Lifetime) in the crypto_handle_incrementing_nontransmitted_counter function within the crypto_tc.c source file. The function is responsible for handling incrementing non-transmitted counters as part of the SDLS-EP cryptographic operations.

When processing data, the function allocates memory dynamically using malloc but fails to ensure that this allocated memory is consistently freed across all code execution paths. In typical short-lived applications, such memory leaks might go unnoticed. However, in the context of spacecraft communications where CryptoLib operates continuously for extended periods processing large volumes of telemetry and command data, this leak accumulates progressively.

The vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker could potentially accelerate the memory exhaustion by sending crafted data streams that trigger the vulnerable code path repeatedly, though the primary concern is organic resource depletion during normal operations.

Root Cause

The root cause lies in improper memory lifecycle management within the crypto_handle_incrementing_nontransmitted_counter function. The function contains code paths where malloc is called to allocate memory buffers, but corresponding free calls are either missing entirely or not executed due to early returns, error conditions, or exception handling that bypasses the deallocation logic.

This pattern is particularly dangerous in embedded systems and long-running services where memory resources are finite and cannot be easily recovered without a system restart. The CryptoLib implementation does not appear to implement a memory pool or garbage collection mechanism that would mitigate such leaks automatically.

Attack Vector

The vulnerability is accessible over the network (Attack Vector: Network) with low attack complexity. An attacker does not require any privileges or user interaction to exploit this vulnerability. The attack scenario involves:

1. Establishing communication with a system running vulnerable CryptoLib
2. Sending data that triggers the crypto_handle_incrementing_nontransmitted_counter function
3. Repeating the process to accelerate memory consumption
4. Eventually causing system performance degradation or complete Denial of Service

The vulnerability can be triggered through normal protocol operations that invoke the affected function, making it difficult to distinguish malicious exploitation from legitimate traffic without proper monitoring.

Detection Methods for CVE-2025-29910

Indicators of Compromise

• Gradual increase in memory consumption by processes using CryptoLib without corresponding workload increase
• System performance degradation over time in spacecraft communication systems
• Unexpected process termination due to out-of-memory conditions
• Memory allocation failures logged by CryptoLib or dependent applications

Detection Strategies

• Implement memory profiling and leak detection tools (e.g., Valgrind, AddressSanitizer) during CryptoLib integration testing
• Monitor process memory usage metrics for applications utilizing CryptoLib functions
• Deploy runtime memory tracking to identify allocation patterns in the crypto_tc.c module
• Review system logs for memory allocation failures or warnings related to CryptoLib operations

Monitoring Recommendations

• Establish baseline memory consumption patterns for CryptoLib-dependent processes and alert on anomalous growth
• Configure automated memory usage thresholds that trigger alerts before resource exhaustion occurs
• Implement periodic process restarts as a temporary mitigation strategy for critical systems until a patch is available
• Enable verbose logging in CryptoLib to track function calls to crypto_handle_incrementing_nontransmitted_counter

How to Mitigate CVE-2025-29910

Immediate Actions Required

• Assess all systems utilizing NASA CryptoLib versions 1.3.3 and prior for exposure to this vulnerability
• Implement memory monitoring and alerting for affected systems to detect early signs of resource exhaustion
• Consider scheduled service restarts for critical systems to prevent memory accumulation from reaching critical levels
• Review the GitHub Security Advisory for updates and additional guidance

Patch Information

As of the publication date, no patched versions of CryptoLib are available. Organizations should monitor the official NASA CryptoLib GitHub repository for security updates and patch releases. When a fix becomes available, immediate testing and deployment is recommended given the potential for DoS conditions in mission-critical communication systems.

Workarounds

• Implement process watchdog mechanisms that automatically restart CryptoLib-dependent services when memory thresholds are exceeded
• Rate-limit incoming data streams to reduce the frequency of vulnerable function invocations
• Deploy wrapper functions that track memory allocations in crypto_handle_incrementing_nontransmitted_counter and ensure proper cleanup
• Consider isolation of CryptoLib processes in containers with memory limits to prevent system-wide impact

# Example memory monitoring configuration for CryptoLib processes
# Add to system monitoring (e.g., cron job or systemd timer)
#!/bin/bash
PROCESS_NAME="cryptolib_process"
MEMORY_THRESHOLD_KB=1048576  # 1GB threshold
CURRENT_MEM=$(ps -o rss= -C $PROCESS_NAME 2>/dev/null | awk '{sum+=$1} END {print sum}')
if [ "$CURRENT_MEM" -gt "$MEMORY_THRESHOLD_KB" ]; then
    logger -p daemon.warning "CryptoLib memory threshold exceeded: ${CURRENT_MEM}KB"
    # Implement appropriate response (alert, restart, etc.)
fi