CVE-2017-9521: Cisco DPC3939 Firmware

Critical severity, CVSS 9.8. EPSS: 3.3% chance of exploitation in the next 30 days.

The Comcast firmware on Cisco DPC3939 (firmware version dpc3939-P20-18-v303r20421733-160420a-CMCST); Cisco DPC3939 (firmware version dpc3939-P20-18-v303r20421746-170221a-CMCST); Cisco DPC3939B (firmware version dpc3939b-v303r204217-150321a-CMCST); Cisco DPC3941T (firmware version DPC3941_2.5s3_PROD_sey); and Arris TG1682G (eMTA&DOCSIS version 10.0.132.SIP.PC20.CT, software version TG1682_2.2p7s2_PROD_sey) devices allows remote attackers to execute arbitrary code via a specific (but unstated) exposed service. NOTE: the scope of this CVE does NOT include the concept of "Unnecessary Services" in general; the scope is only a single service that is unnecessarily exposed, leading to remote code execution. The details of that service might be disclosed at a later date.

Affected products

• Cisco DPC3939 Firmware: version dpc3939-p20-18-v303r20421733-160420a-cmcst only; version dpc3939-p20-18-v303r20421746-170221a-cmcst only
• Cisco DPC3939B Firmware: version dpc3939b-v303r204217-150321a-cmcst only
• Cisco DPC3941T Firmware: version dpc3941_2.5s3_prod_sey only
• Commscope Arris TG1682G Firmware: version 10.0.132.sip.pc20.ct only; version tg1682_2.2p7s2_prod_sey only

Published 2017-07-31. Last modified 2026-06-17.