CVE-2019-18676 Details
An issue was discovered in Squid 3.x and 4.x through 4.8. Due to incorrect input validation, there is a heap-based buffer overflow that can result in Denial of Service to all clients using the proxy. Severity is high due to this vulnerability occurring before normal security checks; any remote client that can reach the proxy port can trivially perform the attack via a crafted URI scheme.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2019-18676
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%).
1.35 Probability of exploitation activity being observed over the next 30 days (80th percentile)
CVSS score for CVE-2019-18676
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-2019-18676
Squid 3.1
Squid 3.1.10
Squid 3.1.11
Squid 3.1.12
Squid 3.1.14
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-2019-18676 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 624,614 75.29%
BR 49,638 5.98%
GB 47,685 5.75%
RO 31,181 3.76%
CA 24,547 2.96%
CN 9,370 1.13%
DE 6,276 0.76%
IN 5,592 0.67%
JP 5,279 0.64%
CH 5,267 0.63%

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CVE-2019-18676 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 123,970 92.24%
Telecommunications 9,887 7.36%
Education 245 0.18%
Media/Entertainment 70 0.05%
Government/Politics 53 0.04%
Business Services 23 0.02%
Retail 21 0.02%
Finance 16 0.01%
Food Production 15 0.01%
Utilities 14 0.01%

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