CVE-2026-21900

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nasa/CryptoLib/commit/2372efd3da1ccb226b4297222e25f41ecc84821d	Patch
https://github.com/nasa/CryptoLib/releases/tag/v1.4.3	Release Notes
https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw	Exploit Vendor Advisory
https://github.com/nasa/CryptoLib/security/advisories/GHSA-4g6v-36fv-qcvw	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nasa:cryptolib:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-10 01:16

Updated : 2026-01-16 16:46

NVD link : CVE-2026-21900

Mitre link : CVE-2026-21900

CVE.ORG link : CVE-2026-21900

JSON object : View

Products Affected

nasa

cryptolib

CWE

CWE-125

Out-of-bounds Read

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