Authentication bypass via JSON parsing differential
Published Apr 2, 2026 · Updated Apr 2, 2026
Authentication bypass in the DS configuration service in TP-Link Tapo C520WS 2.6 allows remote attackers to alter device state. The HTTP authentication check parses a JSON request differently from the action dispatcher, so an appended authentication-exempt action causes privileged DS do actions in the same request to skip authorization. The attacker must reach the camera from the adjacent network; successful requests execute restricted configuration actions without credentials.
Summary
What happened
Authentication bypass in the DS configuration service in TP-Link Tapo C520WS 2.6 allows remote attackers to alter device state. The HTTP authentication check parses a JSON request differently from the action dispatcher, so an appended authentication-exempt action causes privileged DS do actions in the same request to skip authorization. The attacker must reach the camera from the adjacent network; successful requests execute restricted configuration actions without credentials.
The record
- CVE
- CVE-2026-34121
- Published
- Apr 2, 2026
- Updated
- Apr 2, 2026
- Vendor
- TP-Link Systems Inc.
- Product
- Tapo C520WS
- Classifications
- CWE-287, T1210
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 2, 2026CVE publishedPublication date reported by the CVE source.
- Apr 2, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <1.2.4 Build 260326 Rel.24666n
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
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Your stack
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