What is the CVSS score of CVE-2026-21898?

CVE-2026-21898 has a CVSS 3.1 base score of 8.2 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H. EPSS exploitation probability: 0.0%.

Which versions of Cryptolib are affected by CVE-2026-21898?

CVE-2026-21898 presents notable security risk, a out-of-bounds read vulnerability rated CVSS 8.2.

Is there a public PoC exploit available for CVE-2026-21898?

Yes, a public proof-of-concept exploit is available for CVE-2026-21898. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-21898?

Within 7 days: Identify all affected systems and apply vendor patches promptly. Monitor vendor channels for patch availability.

Cryptolib CVE-2026-21898

HIGH

Out-of-bounds Read (CWE-125)

2026-01-10 security-advisories@github.com

Buffer Overflow Information Disclosure Cryptolib

8.2

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

8.2 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

PoC Detected

Jan 15, 2026 - 21:48 vuln.today

Public exploit code

CVE Published

Jan 10, 2026 - 01:16 nvd

HIGH 8.2

DescriptionGitHub Advisory

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, the Crypto_AOS_ProcessSecurity function reads memory without valid bounds checking when parsing AOS frame hashes. This issue has been patched in version 1.4.3.

AnalysisAI

CryptoLib versions prior to 1.4.3 contain an out-of-bounds read vulnerability in the Crypto_AOS_ProcessSecurity function that allows remote attackers to crash spacecraft communications systems when parsing malformed AOS frame hashes. Public exploit code exists for this vulnerability affecting cFS deployments that rely on SDLS-EP for spacecraft-to-ground station security. The vulnerability has high severity due to its denial of service impact on critical space communications infrastructure, and no patch is currently available.

Technical ContextAI

Classified as CWE-125 (Out-of-bounds Read). Affects Cryptolib. 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, the Crypto_AOS_ProcessSecurity function reads memory without valid bounds checking when parsing AOS frame hashes. This issue has been patched in version 1.4.3.