Authenticated ONVIF service crash via excessive XML users
Published Jun 5, 2026 · Updated Jun 5, 2026
Stack-based buffer overflow in Tapo C520WS v2 before 1.2.6 Build 260528 allows remote authenticated users to crash the ONVIF service. The CreateUsers request handler accepts more XML user nodes than its fixed stack storage can hold, causing memory corruption during request processing. Exploitation requires high-privilege credentials and adjacent-network access; the reported consequence is interruption of ONVIF configuration and management functions.
Summary
What happened
Stack-based buffer overflow in Tapo C520WS v2 before 1.2.6 Build 260528 allows remote authenticated users to crash the ONVIF service. The CreateUsers request handler accepts more XML user nodes than its fixed stack storage can hold, causing memory corruption during request processing. Exploitation requires high-privilege credentials and adjacent-network access; the reported consequence is interruption of ONVIF configuration and management functions.
The record
- CVE
- CVE-2026-6239
- Published
- Jun 5, 2026
- Updated
- Jun 5, 2026
- Vendor
- TP-Link Systems Inc.
- Product
- Tapo C520WS
- Classifications
- CWE-121, T1499.004
- Attack vector
- adjacent
- Privileges
- admin
Timeline
How it unfolded
- Jun 5, 2026CVE publishedPublication date reported by the CVE source.
- Jun 5, 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 <1.2.6 Build 260528
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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