CVE-2026-22025: CryptoLib Memory Leak DoS Vulnerability

CVE-2026-22025 Overview

CVE-2026-22025 is a memory leak vulnerability in NASA's CryptoLib, a software-only solution implementing 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. Prior to version 1.4.3, when the KMC (Key Management Client) server returns a non-200 HTTP status code, the cryptography_encrypt() and cryptography_decrypt() functions return immediately without freeing previously allocated buffers, leading to memory exhaustion over time.

Critical Impact

Each failed KMC server request leaks approximately 467 bytes of memory. Repeated failures—whether caused by a malicious server, network issues, or denial-of-service attacks—can gradually exhaust system memory, potentially causing service disruption in critical spacecraft communication systems.

Affected Products

• NASA CryptoLib versions prior to 1.4.3
• Systems implementing CCSDS Space Data Link Security Protocol using CryptoLib
• Spacecraft running core Flight System (cFS) with CryptoLib integration

Discovery Timeline

• 2026-01-10 - CVE CVE-2026-22025 published to NVD
• 2026-01-13 - Last updated in NVD database

Technical Details for CVE-2026-22025

Vulnerability Analysis

This vulnerability is classified as CWE-401 (Missing Release of Memory after Effective Lifetime), a type of memory leak that occurs when dynamically allocated memory is not properly freed. The flaw exists in the error handling path of both cryptography_encrypt() and cryptography_decrypt() functions within CryptoLib.

When the KMC server responds with any HTTP status code other than 200 (success), the affected functions exit prematurely without releasing memory buffers that were allocated earlier in the function execution. This improper resource management creates a cumulative memory leak where each failed request leaves approximately 467 bytes of unfreed memory. In operational environments where network connectivity issues or adversarial conditions may cause repeated failures, this can lead to progressive memory exhaustion.

The vulnerability is exploitable over the network, though it requires specific conditions—namely, the ability to cause the KMC server to return error responses or to intercept and modify network traffic between CryptoLib and the KMC server.

Root Cause

The root cause is improper error handling in the cryptographic functions. When HTTP error responses are received from the KMC server, the code paths designed to handle these errors fail to include proper cleanup routines for previously allocated memory buffers. The immediate return statements bypass the memory deallocation logic that would normally execute during successful operations or proper shutdown sequences.

Attack Vector

The attack vector is network-based and can be exploited under the following scenarios:

1. Malicious KMC Server: An attacker who can control or impersonate the KMC server can deliberately return non-200 status codes to trigger the memory leak
2. Man-in-the-Middle: An attacker positioned between CryptoLib and the KMC server can intercept responses and modify status codes
3. Denial-of-Service Amplification: Network conditions causing legitimate server errors can be exploited or amplified to accelerate memory exhaustion

The following code change shows part of the security patch that addresses compliance documentation (from the commit fixing this vulnerability):

  * @param aad: uint8_t*
  * @return status: uint32_t
  *
- * CCSDS Compliance: CCSDS 355.0-B-2 Section 7.2.3 (AAD Construction)
+ * CCSDS Compliance: CCSDS 355.0-B-2 Section 4.2.3 (AAD Construction)
  **/
 uint32_t Crypto_Prepare_AOS_AAD(const uint8_t *buffer, uint16_t len_aad, const uint8_t *abm_buffer, uint8_t *aad)
 {

Source: GitHub Commit 2372efd3

Detection Methods for CVE-2026-22025

Indicators of Compromise

• Gradual memory consumption increase in processes utilizing CryptoLib
• Elevated frequency of non-200 HTTP responses from KMC server communications
• Unexpected KMC server connection failures or timeout patterns
• System performance degradation correlating with cryptographic operations

Detection Strategies

• Monitor memory usage trends for CryptoLib-dependent processes over extended periods
• Implement HTTP response code logging for all KMC server communications
• Set up alerting for memory consumption thresholds on spacecraft communication systems
• Review application logs for patterns of repeated KMC server errors

Monitoring Recommendations

• Deploy memory profiling tools to track allocation patterns in CryptoLib processes
• Establish baseline memory usage metrics and alert on deviations exceeding normal operational parameters
• Monitor network traffic between CryptoLib components and KMC servers for anomalous error response patterns
• Implement automated health checks that include memory utilization assessments

How to Mitigate CVE-2026-22025

Immediate Actions Required

• Upgrade CryptoLib to version 1.4.3 or later immediately
• If immediate upgrade is not possible, implement monitoring for memory exhaustion conditions
• Review and audit KMC server infrastructure for availability and security
• Consider implementing network-level protections to prevent KMC server impersonation

Patch Information

NASA has released CryptoLib version 1.4.3 which addresses this vulnerability. The patch ensures proper memory deallocation occurs in error handling paths when non-200 HTTP status codes are received from the KMC server.

• Patched Version: CryptoLib v1.4.3
• Security Advisory: GHSA-h74x-vwwr-mm5g
• Patch Commit: 2372efd3da1ccb226b4297222e25f41ecc84821d

Workarounds

• Implement application-level memory monitoring with automatic process restart on threshold breach
• Deploy network filtering to ensure only legitimate KMC server responses reach CryptoLib
• Configure connection retry limits to prevent unbounded memory accumulation from persistent failures
• Establish periodic scheduled restarts of affected services to reclaim leaked memory in environments where immediate patching is not feasible

# Example monitoring script for memory threshold alerting
#!/bin/bash
# Monitor CryptoLib process memory usage
PROCESS_NAME="cryptolib"
THRESHOLD_MB=500

while true; do
    MEM_USAGE=$(ps -o rss= -C $PROCESS_NAME 2>/dev/null | awk '{sum+=$1} END {print sum/1024}')
    if [ ! -z "$MEM_USAGE" ] && [ $(echo "$MEM_USAGE > $THRESHOLD_MB" | bc -l) -eq 1 ]; then
        echo "WARNING: CryptoLib memory usage ($MEM_USAGE MB) exceeds threshold ($THRESHOLD_MB MB)"
        # Add alerting mechanism here
    fi
    sleep 60
done