CVE-2026-71935: DrayTek Corporation Vigorswitch FX2120
High severity, CVSS 7.2. EPSS: 0.7% chance of exploitation in the next 30 days.
Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the webBackupAction function. The vulnerability is caused by repeated string concatenation of the pathN, valueN, key, and option fields into fixed-size stack buffers without total 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.
Affected products
- DrayTek Corporation Vigorswitch FX2120: before 3.9.10 (fixed in 3.9.10)
- DrayTek Corporation Vigorswitch g1280: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch g1282: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch g2100: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch g2121: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch g2280x: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch g2282x: before 2.10.6 (fixed in 2.10.6)
- DrayTek Corporation Vigorswitch g2540x: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch g2540xs: before 3.9.10 (fixed in 3.9.10)
- DrayTek Corporation Vigorswitch g2542x: before 3.10.6 (fixed in 3.10.6)
- DrayTek Corporation Vigorswitch p1280: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p1281x: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p1282: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p2100: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p2121: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p2280x: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p2282x: before 2.10.6 (fixed in 2.10.6)
- DrayTek Corporation Vigorswitch p2540x: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch p2540xs: before 3.9.10 (fixed in 3.9.10)
- DrayTek Corporation Vigorswitch p2542x: before 3.10.6 (fixed in 3.10.6)
- DrayTek Corporation Vigorswitch p2542xh: before 3.10.6 (fixed in 3.10.6)
- DrayTek Corporation Vigorswitch PQ2121X: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch PQ2200XB: before 2.9.10 (fixed in 2.9.10)
- DrayTek Corporation Vigorswitch PQ2300XB: before 2.10.7 (fixed in 2.10.7)
- DrayTek Corporation Vigorswitch PX2060: before 2.9.10 (fixed in 2.9.10)
- and 3 more
Published 2026-08-24. Last modified 2026-08-26.