CVE-2019-9636
CriticalCVSS 9.8Exploitation Probability (EPSS)
Very high risk95th percentile - higher than 95% of all known CVEs
Summary
Python 2.7.x through 2.7.16 and 3.x through 3.7.2 is affected by improper handling of Unicode encoding (with an incorrect netloc) during NFKC normalization. The impact is information disclosure (credentials, cookies, etc. cached against a given hostname). The components are urllib.parse.urlsplit and urllib.parse.urlparse. A specially crafted URL could be incorrectly parsed to locate cookies or authentication data and send that information to a different host.
Risk Assessment
Risk of leaking credentials and cookies to unauthorized hosts, potentially leading to session theft or credential compromise.
Recommendation
Upgrade Python to version 2.7.17, 3.5.10, 3.6.10, 3.7.3 or later, depending on your version.
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- CVE-2019-20907High
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- CVE-2019-5010High
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- CVE-2019-16056High
An issue was discovered in Python through 2.7.16, 3.x through 3.5.7, 3.6.x through 3.6.9, and 3.7.x through 3.7.4. The email module wrongly parses email addresses that contain multiple @ characters. An application that uses the email module and implements some kind of checks on the From/To headers of a message could be tricked into accepting an email address that should be denied. An attack may be the same as in CVE-2019-11340; however, this CVE applies to Python more generally.
Original NVD description (English source)
Python 2.7.x through 2.7.16 and 3.x through 3.7.2 is affected by: Improper Handling of Unicode Encoding (with an incorrect netloc) during NFKC normalization. The impact is: Information disclosure (credentials, cookies, etc. that are cached against a given hostname). The components are: urllib.parse.urlsplit, urllib.parse.urlparse. The attack vector is: A specially crafted URL could be incorrectly parsed to locate cookies or authentication data and send that information to a different host than when parsed correctly. This is fixed in: v2.7.17, v2.7.17rc1, v2.7.18, v2.7.18rc1; v3.5.10, v3.5.10rc1, v3.5.7, v3.5.8, v3.5.8rc1, v3.5.8rc2, v3.5.9; v3.6.10, v3.6.10rc1, v3.6.11, v3.6.11rc1, v3.6.12, v3.6.9, v3.6.9rc1; v3.7.3, v3.7.3rc1, v3.7.4, v3.7.4rc1, v3.7.4rc2, v3.7.5, v3.7.5rc1, v3.7.6, v3.7.6rc1, v3.7.7, v3.7.7rc1, v3.7.8, v3.7.8rc1, v3.7.9.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

