Cyber Resilience

CVE-2019-1937

Auth Bypass in Cisco Ucs Director 6.6.0.0 – 6.6.1.0

Public PoCHigh EPSSAuth Bypass
Published
21 August 2019
Modified
21 November 2024
Patch / advisory
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 0.76 99.5th percentile
Risk Priority 97 floored blend · peak EPSS

Summary

CVE-2019-1937 is a critical-severity Improper Authentication (CWE-287) vulnerability in Cisco Ucs Director. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 0.5% 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

A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Supervisor, Cisco UCS Director, and Cisco UCS Director Express for Big Data could allow an unauthenticated, remote attacker to acquire a valid session token with administrator privileges,…

more

bypassing user authentication. The vulnerability is due to insufficient request header validation during the authentication process. An attacker could exploit this vulnerability by sending a series of malicious requests to an affected device. An exploit could allow the attacker to use the acquired session token to gain full administrator access to the affected device.

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
The vulnerability allows unauthenticated remote attackers to bypass authentication in a web-based management interface and obtain administrator session tokens.
T1078.004 Cloud Accounts Stealthconfidence: HIGH
Successful exploitation grants the attacker a valid administrator session token, enabling use of cloud/management accounts without credentials.
T1133 External Remote Services Persistenceconfidence: MEDIUM
The flaw permits remote attackers to obtain authenticated access via the exposed web management service without valid credentials.
inferred from description + CWE · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2019-1935Same product: Cisco Integrated Management Controller Supervisor
CVE-2020-3248Same product: Cisco Ucs Director
CVE-2020-3250Same product: Cisco Ucs Director
CVE-2020-3247Same product: Cisco Ucs Director
CVE-2020-3251Same product: Cisco Ucs Director
CVE-2020-3243Same product: Cisco Ucs Director
CVE-2020-3239Same product: Cisco Ucs Director
CVE-2023-20238Same vendor: Cisco
CVE-2026-20182Same vendor: Cisco
CVE-2026-20127Same vendor: Cisco

Affected Assets

cisco
integrated management controller supervisor
2.2.0.3 — 2.2.0.6
cisco
ucs director
6.7\(0.0.67265\) · 6.6.0.0 — 6.6.1.0 · 6.7.0.0 — 6.7.1.0
cisco
ucs director express for big data
3.6.0.0 · 3.7.0.0 — 3.7.1.0

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