CVE-2026-34121

Authentication Bypass in DS Configuration Service via HTTP Request Parsing Differential of TP-Link Tapo C520WS

HIGH
8.8
CVSS Score
Published: April 2, 2026 at 05:20 PM UTC
Updated: July 24, 2026 at 09:20 PM UTC
3 products affected across 1 vendorTapo C520WS FirmwareTapo C520WSLink Tapo C520WS

Using Tapo C520WS v2.6 by TP-Link Systems Inc.?

Get instant alerts when new vulnerabilities affect Tapo C520WS v2.6 - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.8
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

An authentication bypass vulnerability within the HTTP handling of the DS configuration service in TP-Link Tapo C520WS v2.6 was identified, due to inconsistent parsing and authorization logic in JSON requests during authentication check. An unauthenticated attacker can append an authentication-exempt action to a request containing privileged DS do actions, bypassing authorization checks. Successful exploitation allows unauthenticated execution of restricted configuration actions, which may result in unauthorized modification of device state.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.2.4
Affected range stops below 1.2.4, so it looks safe — our inference, not a vendor statement
tp-link-tapo-c520ws (same device)
v < 1.2.4 Build 260326 Rel.24666n
Affected range stops below 1.2.4 Build 260326 Rel.24666n, so it looks safe — our inference, not a vendor statement
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
ADJACENT_NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-287

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card