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

Vulnerability from cvelistv5 – Published: 2026-06-05 23:50 – Updated: 2026-06-05 23:50
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
CWE
  • CWE-121 - Stack-based buffer overflow
Assigner
References
Impacted products
Vendor Product Version
TP-Link Systems Inc. Tapo C520WS v2 Affected: 0 , < 1.2.6 Build 260528 (custom)
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        "orgId": "f23511db-6c3e-4e32-a477-6aa17d310630",
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    "dateReserved": "2026-04-13T17:10:22.074Z",
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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