Authenticated Format String Vulnerability in ONVIF Subscribe Service on TP-Link Tapo C520WS
CVE-2026-6242

6.8MEDIUM

Key Information:

Vendor

Tp-link Systems Inc.

Status
Tapo C520ws V2
Vendor
CVE Published:
5 June 2026

What is CVE-2026-6242?

An authenticated format string vulnerability exists in the ONVIF Subscribe service in Tapo C520WS v2 due to improper handling of externally supplied parameters within formatting functions. An attacker may inject crafted format strings into event subscription requests or notification generation path to disrupt normal service execution.

Successful exploitation may cause the event notification service to terminate unexpectedly, resulting in the loss of real-time alarm functionality and disruption of event notifications.

Affected Version(s)

Tapo C520WS v2 0 < 1.2.6 Build 260528

References

https://www.tp-link.com/us/support/download/tapo-c520ws/#...
patch
https://www.tp-link.com/en/support/download/tapo-c520ws/#...
patch
https://www.tp-link.com/us/support/faq/5120/
vendor-advisory

CVSS V4

Score:
6.8
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.