CVE-2017-3857 Details
A vulnerability in the Layer 2 Tunneling Protocol (L2TP) parsing function of Cisco IOS (12.0 through 12.4 and 15.0 through 15.6) and Cisco IOS XE (3.1 through 3.18) could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to insufficient validation of L2TP packets. An attacker could exploit this vulnerability by sending a crafted L2TP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability affects Cisco devices that are running a vulnerable release of Cisco IOS or Cisco IOS XE Software if the L2TP feature is enabled for the device and the device is configured as an L2TP Version 2 (L2TPv2) or L2TP Version 3 (L2TPv3) endpoint. By default, the L2TP feature is not enabled. Cisco Bug IDs: CSCuy82078.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2017-3857
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
1.14 Probability of exploitation activity being observed over the next 30 days (78th percentile)
CVSS score for CVE-2017-3857
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
7.5 High
Products affected by CVE-2017-3857
IOS 15.0\(1\)m4
IOS 15.0\(1\)m5
IOS 15.0\(1\)m6
IOS 15.0\(1\)m7
IOS 15.0\(1\)m8
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Not available
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CVE-2017-3857 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 193 25.16%
KR 73 9.52%
PE 64 8.34%
JP 39 5.08%
AU 35 4.56%
FR 30 3.91%
IN 28 3.65%
BR 26 3.39%
CA 21 2.74%
IE 21 2.74%

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CVE-2017-3857 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 583 87.41%
Telecommunications 76 11.39%
Education 8 1.20%

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