Cyber Resilience

CVE-2024-9999

Auth Bypass

Published
12 November 2024
Modified
15 April 2026
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0042 35th percentile
Risk Priority 48 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2024-9999 is a medium-severity Incorrect Implementation of Authentication Algorithm (CWE-303) vulnerability. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique External Remote Services (T1133); ranked at the 35th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

In WS_FTP Server versions before 8.8.9 (2022.0.9), an Incorrect Implementation of Authentication Algorithm in the Web Transfer Module allows users to skip the second-factor verification and log in with username and password only.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1133 External Remote Services Persistence
Adversaries may leverage external-facing remote services to initially access and/or persist within a network.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-33190Shared CWE-303
CVE-2026-32953Shared CWE-303
CVE-2023-32152Shared CWE-303
CVE-2026-43640Shared CWE-303
CVE-2023-39953Shared CWE-303
CVE-2025-44557Shared CWE-303
CVE-2026-57852Shared CWE-303
CVE-2023-4860Shared CWE-303
CVE-2024-10214Shared CWE-303
CVE-2024-3046Shared CWE-303

Affected Assets

—
In WS_FTP Server
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation at post-design stages directly uncovers incorrect implementations of required authentication algorithms.

Requiring documented development processes, standards, and tools reduces the chance that an established authentication algorithm is coded incorrectly.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require correct implementation of authentication algorithms.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

degrades

Secure authentication control directly requires correct implementation of authentication algorithms.

finds

Security testing can detect flawed authentication implementations but does not prevent them by itself.

degrades

Cryptography control addresses proper use of authentication algorithms but is broader than authentication alone.

prevents

Secure development lifecycle includes verification steps that can catch incorrect authentication implementations.

prevents

Application security requirements can specify correct authentication algorithm use but do not guarantee correct implementation.

prevents

Secure coding practices reduce the likelihood of incorrect authentication algorithm implementation.

References