CVE-2026-21899

4.7 MEDIUM
Published: January 10, 2026 Modified: January 15, 2026
View on NVD

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/nasa/CryptoLib/releases/tag/v1.4.3
Source: security-advisories@github.com
Release Notes
https://github.com/nasa/CryptoLib/security/advisories/GHSA-wc29-5hw7-mpj8
Source: security-advisories@github.com
Exploit Vendor Advisory

2 reference(s) from NVD

Quick Stats

CVSS v3 Score
4.7 / 10.0
EPSS (Exploit Probability)
0.0%
8th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

nasa