CVE-2009-1891 Details
The mod_deflate module in Apache httpd 2.2.11 and earlier compresses large files until completion even after the associated network connection is closed, which allows remote attackers to cause a denial of service (CPU consumption).
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2009-1891
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%).
17.11 Probability of exploitation activity being observed over the next 30 days (97th percentile)
CVSS score for CVE-2009-1891
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.
7.1 High
Products affected by CVE-2009-1891
HTTP Server 2.0.60
HTTP Server 2.0.61
HTTP Server 2.0.63
HTTP Server 2.2.0
HTTP Server 2.2.1
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
More on DVE scores

CVE-2009-1891 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 53,852 22.97%
JP 33,458 14.27%
DE 33,150 14.14%
TW 23,274 9.93%
IT 6,731 2.87%
FR 5,640 2.41%
KR 5,572 2.38%
ES 4,528 1.93%
CN 4,186 1.79%
CA 4,025 1.72%

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CVE-2009-1891 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 73,008 47.88%
Telecommunications 72,913 47.82%
Education 2,259 1.48%
Government/Politics 818 0.54%
Business Services 726 0.48%
Utilities 476 0.31%
Healthcare/Wellness 428 0.28%
Media/Entertainment 394 0.26%
Consumer Goods 263 0.17%
Legal 228 0.15%

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