CVE-2026-6239 (GCVE-0-2026-6239)

Vulnerability from cvelistv5 – Published: 2026-06-05 23:50 – Updated: 2026-06-08 13:07
VLAI
Title
Authenticated Stack-based Buffer Overflow in ONVIF CreateUsers Service in TP-Link Tao C520WS
Summary
A stack‑based buffer overflow vulnerability exists in Tapo C520WS v2 in the ONVIF CreateUsers service, where the device fails to properly validate the number of XML user nodes during request processing. An authenticated attacker can send a specially crafted ONVIF request containing an excessive number of user entries to trigger memory corruption. Successful exploitation may cause the ONVIF management service to terminate unexpectedly, resulting in a denial‑of‑service (DoS) condition that disrupts device configuration and management functions.
Severity
6.8 (Medium)
CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-08 13:07 UTC
CWE
  • CWE-121 - Stack-based buffer overflow
Assigner
TPLink CNA under the mitre root
CNA scorecard B 87/100 over 106 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
TP-Link Systems Inc. Tapo C520WS v2 Affected: 0 , < 1.2.6 Build 260528 (custom)
guessed Create a notification for this product.
Show details on NVD website
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