Tapo C520ws FirmwareOperating system · Tp Link

CVE-2026-34120

MEDIUM · 6.5 CVSS v3.1 Published 2026-04-02
Fix available
A fix is available. Upgrade to 1.2.4 or later.
See remediation →
70/100
Remediation priority · Elevated
No privileges 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
A heap-based buffer overflow vulnerability was identified in TP-Link Tapo C520WS v2.6 within the asynchronous parsing of local video stream content due to insufficient alignment and validation of buffer boundaries when processing streaming inputs.An attacker on the same network segment could trigger heap memory corruption conditions by sending crafted payloads that cause write operations beyond allocated buffer boundaries.  Successful exploitation causes a Denial-of-Service (DoS) condition, causing the device’s process to crash or become unresponsive.

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

Heap-based buffer overflow in TP-Link Tapo C520WS v2.6 during asynchronous parsing of local video stream content. Insufficient boundary validation when processing streaming inputs allows an attacker on the same network segment to send crafted payloads that write beyond allocated buffer boundaries, causing heap memory corruption and process crash/DoS.

MitigationApply network segmentation to isolate the device from untrusted network segments; monitor for vendor firmware updates from TP-Link and apply when available.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Tapo C520ws FirmwareOperating system
Affected:< 1.2.4

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
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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
    Access the device management interface or check the device label to verify the exact model is TP-Link Tapo C520WS
    Affected if Device is not a TP-Link Tapo C520WS
  2. Identify installed firmware version
    Log into the Tapo app or web interface and navigate to Device Settings > Device Info to view the current firmware version. Compare against the affected range of versions below 1.2.4
    Affected if Firmware version is 1.2.3 or lower, or any version less than 1.2.4
  3. Verify video streaming feature is active
    Check if the device has live video streaming enabled through the Tapo app or ONVIF/RTSP configuration. The vulnerability exists in the video stream parsing logic, so streaming must be enabled for exploitation
    Affected if Video streaming functionality is disabled on the device
  4. Assess network accessibility
    Determine if the device is accessible from network segments where untrusted attackers could reside. Check if the device management interface is exposed to broader networks beyond the local trusted segment
    Affected if Device is reachable from untrusted network segments or the device lacks network isolation

The device is affected if it is a TP-Link Tapo C520WS running firmware version 1.2.3 or below (prior to 1.2.4) with video streaming enabled and accessible from a network segment where an attacker could send crafted payloads.

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.

dbcve · scoped
Upgrade available Upgrade to 1.2.4 or later
Fixed in 1.2.4
Interim mitigation

Apply network segmentation to isolate the device from untrusted network segments; monitor for vendor firmware updates from TP-Link and apply when available.

Recommended fix High confidence

Firmware 1.2.4

  1. Confirm the device model is TP-Link Tapo C520WS
  2. Check the current firmware version on the device through the Tapo app or device settings
  3. Download firmware version 1.2.4 or later from the official TP-Link support website (support.tp-link.com)
  4. Follow TP-Link's standard firmware update procedure, typically through the Tapo mobile application or web interface
  5. Verify the firmware update was successful by checking the installed version

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Tapo C520ws Firmware Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,980
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,968.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-34120 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2026-34120 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data