CVE-2026-21899

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, in base64urlDecode, padding-stripping dereferences input[inputLen - 1] before checking that inputLen > 0 or that input != NULL. For inputLen == 0, this becomes an OOB read at input[-1], potentially crashing the process. If input == NULL and inputLen == 0, it dereferences NULL - 1. This issue has been patched in version 1.4.3.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/nasa/CryptoLib/releases/tag/v1.4.3	Release Notes
https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-01-10 01:16

Updated : 2026-01-15 21:45

NVD link : CVE-2026-21899

Mitre link : CVE-2026-21899

CVE.ORG link : CVE-2026-21899

JSON object : View

Products Affected

nasa

cryptolib

CWE

CWE-125

Out-of-bounds Read

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