An exploitable firmware modification vulnerability was discovered in certain Netgear products. The data integrity of the uploaded firmware image is ensured with a fixed checksum number. Therefore, an attacker can conduct a MITM attack to modify the user-uploaded firmware image and bypass the checksum verification. This affects WNR612v2 Wireless Routers 1.0.0.3 and earlier, DGN1000v3 Modem Router 1.0.0.22 and earlier, D6100 WiFi DSL Modem Routers 1.0.0.63 and earlier, WNR1000v2 Wireless Routers 1.1.2.60 and earlier, XAVN2001v2 Wireless-N Extenders 0.4.0.7 and earlier, WNR2200 Wireless Routers 1.0.1.102 and earlier, WNR2500 Wireless Routers 1.0.0.34 and earlier, R8900 Smart WiFi Routers 1.0.3.6 and earlier, and R9000 Smart WiFi Routers 1.0.3.6 and earlier.