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CVE-2017-9521: Cisco Dpc3939 Firmware: Remote code execution

CVE-2017-9521 is rated critical with a CVSS v3.1 base score of 9.8 and affects Cisco Dpc3939 Firmware, along with 1 other product in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

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.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Affected products

  • Cisco Dpc3939 Firmware: dpc3939-p20-18-v303r20421733-160420a-cmcst; dpc3939-p20-18-v303r20421746-170221a-cmcst
  • Cisco Dpc3939b Firmware: dpc3939b-v303r204217-150321a-cmcst
  • Cisco Dpc3941t Firmware: dpc3941_2.5s3_prod_sey
  • Commscope Arris Tg1682g Firmware: 10.0.132.sip.pc20.ct; tg1682_2.2p7s2_prod_sey

References