CVE-2026-21900
January 10, 2026
CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. Prior to version 1.4.3, an out-of-bounds heap read vulnerability in cryptography_encrypt() occurs when parsing JSON metadata from KMC server responses. The flawed strtok iteration pattern uses ptr + strlen(ptr) + 1 which reads one byte past allocated buffer boundaries when processing short or malformed metadata strings. This issue has been patched in version 1.4.3.
Affected Packages
https://github.com/nasa/CryptoLib.git (GITHUB):
Affected version(s) >=v0.1-engineering-release <v1.4.3Fix Suggestion:
Update to version v1.4.3https://github.com/nasa/CryptoLib.git (GITHUB):
Affected version(s) >=v0.1-engineering-release <v1.4.3Fix Suggestion:
Update to version v1.4.3https://github.com/nasa/CryptoLib.git (GITHUB):
Affected version(s) >=v0.1-engineering-release <v1.4.3Fix Suggestion:
Update to version v1.4.3Related ResourcesĀ (3)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.2
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Out-of-bounds Read
EPSS
Base Score:
0.06