CVE-2011-3639 Details
The mod_proxy module in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x before 2.2.18, when the Revision 1179239 patch is in place, does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers by using the HTTP/0.9 protocol with a malformed URI containing an initial @ (at sign) character. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-3368.
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Exploit prediction scoring system (EPSS) score for CVE-2011-3639
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%).
16.68 Probability of exploitation activity being observed over the next 30 days (95th percentile)
CVSS score for CVE-2011-3639
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.
4.3 Medium
Products affected by CVE-2011-3639
HTTP Server 2.0.50
HTTP Server 2.0.51
HTTP Server 2.0.52
HTTP Server 2.0.53
HTTP Server 2.0.54
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-2011-3639 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 144,483 22.40%
JP 94,768 14.69%
DE 79,636 12.35%
TW 27,377 4.24%
RU 26,942 4.18%
KR 26,174 4.06%
GB 19,949 3.09%
FR 19,238 2.98%
IT 18,178 2.82%
CN 17,178 2.66%

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CVE-2011-3639 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 219,582 59.02%
Telecommunications 125,783 33.81%
Education 9,225 2.48%
Government/Politics 3,857 1.04%
Business Services 2,794 0.75%
Utilities 1,929 0.52%
Media/Entertainment 1,231 0.33%
Food Production 1,115 0.30%
Transportation 1,010 0.27%
Healthcare/Wellness 834 0.22%

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