CVE-2018-14647
HighCVSS 7.5Exploitation Probability (EPSS)
Very high risk96th percentile - higher than 96% of all known CVEs
Summary
Python's elementtree C accelerator failed to initialize Expat's hash salt during initialization. This could make it easy to conduct denial of service attacks against Expat by constructing an XML document that causes pathological hash collisions in Expat's internal data structures, consuming large amounts of CPU and RAM. The vulnerability exists in Python versions 3.7.0, 3.6.0 through 3.6.6, 3.5.0 through 3.5.6, 3.4.0 through 3.4.9, 2.7.0 through 2.7.15.
Risk Assessment
Risk of DoS attacks that can overload the system, causing service unavailability and significant resource consumption.
Recommendation
It is recommended to upgrade Python to a version that includes the fix for Expat hash salt initialization.
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Original NVD description (English source)
Python's elementtree C accelerator failed to initialise Expat's hash salt during initialization. This could make it easy to conduct denial of service attacks against Expat by constructing an XML document that would cause pathological hash collisions in Expat's internal data structures, consuming large amounts CPU and RAM. The vulnerability exists in Python versions 3.7.0, 3.6.0 through 3.6.6, 3.5.0 through 3.5.6, 3.4.0 through 3.4.9, 2.7.0 through 2.7.15.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

