The Comcast firmware on Cisco DPC3939 (firmware version dpc3939-P20-18-v303r20421733-160420a-CMCST) and DPC3939 (firmware version dpc3939-P20-18-v303r20421746-170221a-CMCST) devices allows remote attackers to discover the CM MAC address by connecting to the device's xfinitywifi hotspot.
CVE-2017-9477
MEDIUMNVD 6.56.5—
EchelonGraph scoreMEDIUM confidence
Score 6.5 from GitHub Security Advisory published 2022-05-17. NVD baseline CVSS 6.5; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
6.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 1%CVSS: 6.5Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 6.5(medium)
- EPSS
- 59.8%
- KEV
- Not listed
Published
July 31, 2017
Last Modified
May 13, 2026
References (2)
Frequently asked(5)
What is CVE-2017-9477?
CVE-2017-9477 is a medium vulnerability published on July 31, 2017. The Comcast firmware on Cisco DPC3939 (firmware version dpc3939-P20-18-v303r20421733-160420a-CMCST) and DPC3939 (firmware version dpc3939-P20-18-v303r20421746-170221a-CMCST) devices allows remote attackers to discover the CM MAC address by connecting to the device's xfinitywifi hotspot.
When was CVE-2017-9477 disclosed?
CVE-2017-9477 was first published in the National Vulnerability Database on July 31, 2017, with the most recent update on May 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2017-9477 actively exploited?
CVE-2017-9477 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 59.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2017-9477?
CVE-2017-9477 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2017-9477?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2017-9477, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2017-9477
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