Cyber Resilience

CVE-2018-17153

Auth Bypass in Western Digital My Cloud Wdbctl0020Hwt Firmware ≤ 2.30.196

Public PoCHigh EPSSAuth Bypass
Published
18 September 2018
Modified
21 November 2024
CVSS Score v3 9.8
Click a component to see what it means
Raw vectorCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.87 99.7th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2018-17153 is a critical-severity Improper Authentication (CWE-287) vulnerability in Western Digital My Cloud Pr4100. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

It was discovered that the Western Digital My Cloud device before 2.30.196 is affected by an authentication bypass vulnerability. An unauthenticated attacker can exploit this vulnerability to authenticate as an admin user without needing to provide a password, thereby gaining…

more

full control of the device. (Whenever an admin logs into My Cloud, a server-side session is created that is bound to the user's IP address. After the session is created, it is possible to call authenticated CGI modules by sending the cookie username=admin in the HTTP request. The invoked CGI will check if a valid session is present and bound to the user's IP address.) It was found that it is possible for an unauthenticated attacker to create a valid session without a login. The network_mgr.cgi CGI module contains a command called "cgi_get_ipv6" that starts an admin session -- tied to the IP address of the user making the request -- if the additional parameter "flag" with the value "1" is provided. Subsequent invocation of commands that would normally require admin privileges now succeed if an attacker sets the username=admin cookie.

CWE(s)

Related Threats

Likely ATT&CK TechniquesAI

Techniques this vulnerability likely enables, inferred from its description, weakness type, and attributed-actor tradecraft. Confidence is per-technique.

T1190 Exploit Public-Facing Application Initial Accessconfidence: HIGH
Unauthenticated attacker bypasses authentication on a network-exposed CGI endpoint to gain admin access.
T1078.001 Default Accounts Stealthconfidence: HIGH
Vulnerability allows creation of a valid admin session without credentials, effectively using a default or implicit privileged account context.
T1133 External Remote Services Persistenceconfidence: MEDIUM
Bypass enables remote administrative access via exposed web/CGI service without authentication.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2016-10108Same vendor: Western Digital
CVE-2026-5270Shared CWE-287
CVE-2026-10167Shared CWE-287
CVE-2023-3597Shared CWE-287
CVE-2024-44127Shared CWE-287
CVE-2024-0799Shared CWE-287
CVE-2023-1935Shared CWE-287
CVE-2023-4415Shared CWE-287
CVE-2025-68402Shared CWE-287
CVE-2024-45750Shared CWE-287

Affected Assets

western digital
my cloud wdbctl0020hwt firmware
≤ 2.30.196
western digital
my cloud pr4100
≤ 2.30.196
western digital
my cloud pr2100 firmware
≤ 2.30.196
western digital
my cloud mirror gen 2 firmware
≤ 2.30.196
western digital
my cloud mirror firmware
≤ 2.30.196
western digital
my cloud ex4100
≤ 2.30.196
western digital
my cloud ex4 firmware
≤ 2.30.196
western digital
my cloud ex2100 firmware
≤ 2.30.196
western digital
my cloud ex2 ultra firmware
≤ 2.30.196
western digital
my cloud ex2 firmware
≤ 2.30.196
+2 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.4.4
  • V6.5.4
  • V6.5.5
  • V6.5.7

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-287

Detects unauthorized successful logons resulting from improper authentication implementations.

addresses: CWE-287

Documented procedures ensure personnel are trained on authentication mechanisms, tangibly lowering the risk of improper authentication being exploited.

addresses: CWE-287

Security awareness training instructs users on secure authentication practices and avoiding credential compromise.

addresses: CWE-287

Training on authentication mechanisms and best practices decreases the occurrence of improper authentication.

addresses: CWE-287

Non-repudiation requires strong authentication mechanisms to irrefutably attribute performed actions to specific individuals or processes.

addresses: CWE-287

Session content review can reveal authentication bypasses or failures in session establishment.

addresses: CWE-287

Review of authentication-related audit records can detect improper authentication mechanisms or bypasses.

addresses: CWE-287

Assessments check authentication mechanisms for correct implementation and effectiveness, reducing successful authentication bypass attempts.

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.AA-03 mostly match
prevents

PR.AA-03 directly enforces authentication mechanisms that eliminate most improper-authentication defects, yet CWE-287 spans additional vectors (missing checks, flawed protocols, session handling) that one control does not fully close.

PR.AA-04 mostly match
prevents

PR.AA-04 directly enables verification of identity assertions (mostly preventing CWE-287 in that scope) yet leaves many other authentication failure modes unaddressed (only partial prevention overall).

PR.AA-01 partial match
prevents

PR.AA-01 supplies and governs credentials/tokens that authentication relies on, removing some weak-credential cases, yet leaves verification logic, missing checks, and protocol flaws untouched.

PR.AA-02 partial match
prevents

PR.AA-02 ensures valid enrollment and unique credential binding, which reduces some improper-auth risks at issuance time but leaves runtime claim verification untouched, so each direction only partially addresses the other.

PR.PS-01 partial match
prevents

PR.PS-01 can enforce auth-related settings via hardened baselines and default reviews, blocking some config-based instances of CWE-287, yet leaves code-level auth flaws untouched so neither direction reaches mostly.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate some known auth vulnerabilities after deployment (partial forward) but does not address the design or implementation of authentication logic itself (none reverse).

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.

prevents

Requiring authentication methods whose strength matches the sensitivity of the data and mandating multi-factor authentication directly blocks attempts to access resources without proving identity.

prevents

Verifying user identity before issuing replacement credentials and forcing changes after compromise reduces the likelihood that authentication bypass can be achieved through stolen or weak credentials.

prevents

Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.

mitigates

Requiring authentication mechanisms and technical parameters for secure connections ensures that network services verify user identity before granting access, preventing exploitation of missing or weak authentication.

prevents

Security requirements specified early and verified through testing drive the consistent implementation of authentication mechanisms, decreasing the likelihood that authentication steps are omitted or incorrectly applied.

prevents

Defining the required level of trust in entity identity and the authentication mechanisms to achieve it ensures that authentication is explicitly addressed rather than omitted.

References