CVE-2026-71937

Description

Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the poe_schedule_profile function. The vulnerability is caused by repeated concatenation of the start_date, start_time, duration_time, how_often, weekdays, monthly_date, and cycle_duration fields into small fixed-size buffers without proper length checks. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface.

CVSS Vector

References

• https://www.draytek.com/about/security-advisory/multiple-vulnerabilities-in-vigorswitch-series-august-2026/
• https://www.vulncheck.com/advisories/draytek-vigorswitch-multiple-models-buffer-overflow-via-poe-schedule-profile