CVE-2026-111855: Tektronix 3 Series Mdo

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

An issue was discovered on Tektronix 3 Series MDO devices before 1.21.1. A path traversal vulnerability exists in the web management interface of the device. Insufficient validation of user-supplied file paths allows remote attackers to read arbitrary files accessible to the application. Depending on configuration, exploitation may be possible without authentication.

Affected products

• Tektronix 3 Series Mdo: before 1.21.1 (fixed in 1.21.1)

Published 2026-10-17. Last modified 2026-10-17.