Cyber Resilience

CVE-2026-21528

Microsoft Azure Iot Explorer ≤ 0.15.13

Published
10 February 2026
Modified
19 February 2026
Patch / advisory
View advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0051 41th percentile
Risk Priority 51 floored blend · peak EPSS

Summary

CVE-2026-21528 is a medium-severity Binding to an Unrestricted IP Address (CWE-1327) vulnerability in Microsoft Azure Iot Explorer. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Cloud Instance Metadata API (T1552.005); ranked at the 41th 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 AC-3 (Access Enforcement) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability Data

Binding to an unrestricted ip address in Azure IoT Explorer allows an unauthorized attacker to disclose information over a network.

CWE(s)
CWE-1327CWE-668

Related Threats

MITRE ATT&CK Enterprise Techniques

T1552.005 Cloud Instance Metadata API Credential Access
Adversaries may attempt to access the Cloud Instance Metadata API to collect credentials and other sensitive data.
attack.mitre.org →
T1552.007 Container API Credential Access
Adversaries may gather credentials via APIs within a containers environment.
attack.mitre.org →
T1039 Data from Network Shared Drive Collection
Adversaries may search network shares on computers they have compromised to find files of interest.
attack.mitre.org →
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.
attack.mitre.org →
T1530 Data from Cloud Storage Collection
Adversaries may access data from cloud storage.
attack.mitre.org →
T1552 Unsecured Credentials Credential Access
Adversaries may search compromised systems to find and obtain insecurely stored credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-29355Same vendor: Microsoft
CVE-2023-32019Same vendor: Microsoft
CVE-2023-36429Same vendor: Microsoft
CVE-2023-24906Same vendor: Microsoft
CVE-2023-24863Same vendor: Microsoft
CVE-2023-24866Same vendor: Microsoft
CVE-2023-23409Same vendor: Microsoft
CVE-2023-36596Same vendor: Microsoft
CVE-2023-23394Same vendor: Microsoft
CVE-2023-21687Same vendor: Microsoft

Affected Assets

microsoft
azure iot explorer
≤ 0.15.13

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 · 7 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

AC-3 Access Enforcement good match

Access enforcement directly stops resources from being reachable by actors outside the intended control sphere.

AC-4 Information Flow Enforcement good match

Information flow enforcement structurally prevents unintended cross-sphere data or resource exposure.

AC-6 Least Privilege good match

Least privilege reduces the set of actors that can reach a resource, limiting wrong-sphere exposure.

CM-6 Configuration Settings good match

Establishes the most restrictive configuration settings, which would require binding only to specific addresses rather than 0.0.0.0.

AC-16 Security and Privacy Attributes partial match

Security attributes enable correct sphere assignment and subsequent enforcement decisions.

CM-7 Least Functionality partial match

Enforces least functionality by prohibiting unnecessary network exposure such as unrestricted listening addresses.

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-01 full match
prevents

Configuration management enforces restricted bind addresses, covering the weakness completely but only one aspect of overall hardening.

PR.AA-05 mostly match
prevents

Enforcing least-privilege authorizations directly prevents resources from being exposed outside their intended control sphere.

PR.IR-01 mostly match
prevents

Network protection controls directly prevent exposure via unrestricted binds while fixing the weakness addresses only one vector of unauthorized access.

ID.AM-03 partial match
prevents

Documenting authorized network flows informs correct bind decisions and reduces the chance of 0.0.0.0 usage.

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.

A.8.21 Security of network services mostly match
prevents

Security of network services includes hardening service bindings to prevent exposure on all interfaces.

A.8.27 Secure system architecture and engineering principles mostly match
prevents

Secure architecture principles discourage exposing services on all interfaces, though the control is broader than this single weakness.

A.8.20 Networks security partial match
mitigates

Network security controls directly require restricting listening interfaces to specific addresses rather than 0.0.0.0.

A.8.22 Segregation of networks partial match
mitigates

Network segregation can limit the blast radius of an unrestricted binding but does not prevent the binding itself.

A.8.28 Secure coding partial match
prevents

Secure coding guidance can catch hard-coded 0.0.0.0 bindings during development but is not the primary mitigation.

A.5.9 Inventory of information and other associated assets none match
none

Requiring owners to manage the full asset life cycle and remove assets from the inventory upon secure disposal helps prevent resources from being inadvertently exposed outside their intended security sphere.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-668
  • V-248823 OL 8 must not have the telnet-server package installed. prevents CWE-668
RHEL 7 (1 rule)
  • V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-668
Windows 10 (1 rule)
  • V-220967 The Debug programs user right must only be assigned to the Administrators group. prevents CWE-668
Windows 11 (1 rule)
  • V-253490 The "Debug programs" user right must only be assigned to the Administrators group. prevents CWE-668
Windows Server 2016 (1 rule)
  • V-225079 The Debug programs user right must only be assigned to the Administrators group. prevents CWE-668
Windows Server 2019 (1 rule)
  • V-205757 Windows Server 2019 Debug programs: user right must only be assigned to the Administrators group. prevents CWE-668
Windows Server 2022 (1 rule)
  • V-254500 Windows Server 2022 debug programs user right must only be assigned to the Administrators group. prevents CWE-668

References