CVE-2026-6239 (GCVE-0-2026-6239)
Vulnerability from cvelistv5 – Published: 2026-06-05 23:50 – Updated: 2026-06-08 13:07
VLAI
EPSS
VEX
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
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-121 - Stack-based buffer overflow
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://www.tp-link.com/us/support/download/tapo-… | patch |
| https://www.tp-link.com/en/support/download/tapo-… | patch |
| https://www.tp-link.com/us/support/faq/5120/ | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| TP-Link Systems Inc. | Tapo C520WS v2 |
Affected:
0 , < 1.2.6 Build 260528
(custom)
|
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- 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.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- 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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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
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