dbcve.org
Improper AuthenticationWeakness · CWE-287

CVE-2026-34123

HIGH · 7.0 CVSS v4.0 Published 2026-06-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
72/100
Remediation priority · Elevated
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
On Tapo C520WS v2, restricted accounts (for example, hub users) are intended to execute only a limited set of low‑sensitivity operations. Due to a logic flaw in the device’s API authorization mechanism, an attacker can craft requests that leverage legitimate “method mapping” behavior to bypass whitelist restrictions, allowing restricted operations to be masked as permitted requests and executed. Successful exploitation may allow an attacker (with access to a restricted account) to execute unauthorized sensitive operations.  Depending on the operation invoked, impact could include device resets, unintended configuration changes, or disruption of normal operation, leading to loss of availability and integrity of the device.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

The Tapo C520WS v2 contains a logic flaw in its API authorization mechanism where restricted hub accounts can bypass whitelist restrictions through method mapping. Attackers can craft requests that mask unauthorized operations as permitted ones by leveraging legitimate API behavior, enabling sensitive operations like device resets or configuration changes.

MitigationApply vendor firmware updates when available; until then, restrict network access to the device and avoid using shared or hub accounts for untrusted users.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Adjacent
Complexity
Low
Privileges
Low
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm device model and firmware version
    Access the Tapo C520WS v2 web interface or mobile app and navigate to Settings > Device Info to retrieve the exact model number and firmware version. Alternatively, query the device's API endpoint /api/device/info for model and firmware fields.
    Affected if Device model is C520WS with firmware version prior to any vendor-provided fix, or model cannot be verified as updated.
  2. Identify configured hub users and their roles
    Check the Tapo app or web interface under Settings > User Management or Hub Settings to enumerate all configured users and their assigned permission levels. Note any users marked as 'restricted', 'limited', or with reduced privileges.
    Affected if There are hub users configured with restricted permissions (e.g., guest users, limited-access accounts).
  3. Inspect API authorization configuration for method mapping
    Examine the device's API configuration files or API responses for endpoint behavior. Send a test API request to an endpoint that should be restricted (e.g., /api/device/reset or /api/hub/config) using credentials from a restricted user account. Check if the request succeeds by being mapped to a lower-privilege method.
    Affected if Restricted user accounts can successfully execute high-sensitivity operations (device reset, configuration changes) through API endpoints that should be blocked.
  4. Verify whitelist enforcement on sensitive endpoints
    Review the API access control list or user permission matrix for the device. Specifically test whether endpoints for device reset, hub configuration, or user management are properly blocked for non-administrative accounts.
    Affected if Sensitive endpoints (reset, config changes, user management) are accessible to or executable by accounts that should be restricted by the whitelist.

A user is affected if they have a Tapo C520WS v2 device with restricted hub users configured, and those restricted users can bypass whitelist restrictions to perform sensitive operations through the API method mapping behavior.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply vendor firmware updates when available; until then, restrict network access to the device and avoid using shared or hub accounts for untrusted users.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
21.0 hours of engineering $3,680
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-34123 in production — separate from our analysis above.

No notes yet

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What this is

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What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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