Cyber Resilience

CVE-2026-59309

Auth Bypass in Vmware Vcenter Server ≤ 8.0

Published
30 July 2026
Modified
25 August 2026
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.079 94th percentile
Risk Priority 79 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-2026-59309 is a critical-severity Incorrect Implementation of Authentication Algorithm (CWE-303) vulnerability in Vmware Vcenter Server. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique External Remote Services (T1133); ranked in the top 6% of CVEs by exploit likelihood; 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

VMware vCenter contains an authentication bypass vulnerability in the VMware Directory Service. A malicious actor with network access to vCenter may exploit this issue to bypass authentication and gain unauthorized access to the system.

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-2026-59310Same product: Vmware Cloud Foundation
CVE-2020-3952Same product: Vmware Vcenter Server
CVE-2021-22005Same product: Vmware Cloud Foundation
CVE-2021-21972Same product: Vmware Cloud Foundation
CVE-2021-21973Same product: Vmware Cloud Foundation
CVE-2025-22225Same product: Vmware Cloud Foundation
CVE-2024-38813Same product: Vmware Cloud Foundation
CVE-2021-21985Same product: Vmware Cloud Foundation
CVE-2024-37080Same product: Vmware Cloud Foundation
CVE-2024-37079Same product: Vmware Cloud Foundation

Affected Assets

vmware
vcenter server
8.0 · ≤ 8.0 · 9.0 — 9.0.2.0100 · 9.1 — 9.1.0.0300

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 partial 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

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.

finds

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

prevents

Secure authentication control directly requires correct implementation of authentication algorithms.

References