CVE-2026-6239: CWE-121 Stack-based buffer overflow in TP-Link Systems Inc. Tapo C520WS v2
CVE-2026-6239 is a stack-based buffer overflow vulnerability in the ONVIF CreateUsers service of TP-Link Tapo C520WS v2 devices. The vulnerability arises because the device does not properly validate the number of XML user nodes in requests. An authenticated attacker can exploit this by sending a specially crafted ONVIF request with excessive user entries, causing memory corruption. Successful exploitation results in the ONVIF management service terminating unexpectedly, leading to a denial-of-service (DoS) condition that disrupts device configuration and management. The vulnerability has a CVSS 4. 0 base score of 6. 8, indicating medium severity. There is no information on available patches or official remediation at this time.
AI Analysis
Technical Summary
This vulnerability is a stack-based buffer overflow (CWE-121) in the ONVIF CreateUsers service of the TP-Link Tapo C520WS v2 device. It occurs due to improper validation of the number of XML user nodes during request processing. An attacker with authenticated access can send a crafted ONVIF request containing an excessive number of user entries, triggering memory corruption. The impact is a denial-of-service condition caused by the termination of the ONVIF management service, which affects device configuration and management capabilities. No patch or official fix has been disclosed, and no known exploits are reported in the wild.
Potential Impact
Exploitation leads to denial-of-service by causing the ONVIF management service to crash, disrupting device configuration and management. There is no indication of privilege escalation, data disclosure, or remote code execution. The attacker must be authenticated to exploit this vulnerability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict authenticated access to the ONVIF management interface to trusted users only to reduce risk.
CVE-2026-6239: CWE-121 Stack-based buffer overflow in TP-Link Systems Inc. Tapo C520WS v2
Description
CVE-2026-6239 is a stack-based buffer overflow vulnerability in the ONVIF CreateUsers service of TP-Link Tapo C520WS v2 devices. The vulnerability arises because the device does not properly validate the number of XML user nodes in requests. An authenticated attacker can exploit this by sending a specially crafted ONVIF request with excessive user entries, causing memory corruption. Successful exploitation results in the ONVIF management service terminating unexpectedly, leading to a denial-of-service (DoS) condition that disrupts device configuration and management. The vulnerability has a CVSS 4. 0 base score of 6. 8, indicating medium severity. There is no information on available patches or official remediation at this time.
CVSS v4.0
Score 6.8medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability is a stack-based buffer overflow (CWE-121) in the ONVIF CreateUsers service of the TP-Link Tapo C520WS v2 device. It occurs due to improper validation of the number of XML user nodes during request processing. An attacker with authenticated access can send a crafted ONVIF request containing an excessive number of user entries, triggering memory corruption. The impact is a denial-of-service condition caused by the termination of the ONVIF management service, which affects device configuration and management capabilities. No patch or official fix has been disclosed, and no known exploits are reported in the wild.
Potential Impact
Exploitation leads to denial-of-service by causing the ONVIF management service to crash, disrupting device configuration and management. There is no indication of privilege escalation, data disclosure, or remote code execution. The attacker must be authenticated to exploit this vulnerability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict authenticated access to the ONVIF management interface to trusted users only to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- TPLink
- Date Reserved
- 2026-04-13T17:10:22.074Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a23675be29bf47b50dbe8d3
Added to database: 6/6/2026, 12:18:35 AM
Last enriched: 6/6/2026, 12:33:49 AM
Last updated: 6/6/2026, 2:55:08 AM
Views: 9
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