CVE-2016-9015
lowpriority · track · 15EPSS 0.008 · 55 %ileEUUSEPSS · scored 2026-10-27
Versions 1.17 and 1.18 of the Python urllib3 library suffer from a vulnerability that can cause them, in certain configurations, to not correctly validate TLS certificates. This places users of the library with those configurations at risk of man-in-the-middle and information leakage attacks. This vulnerability affects users using versions 1.17 and 1.18 of the urllib3 library, who are using the optional PyOpenSSL support for TLS instead of the regular standard library TLS backend, and who are using OpenSSL 1.1.0 via PyOpenSSL. This is an extremely uncommon configuration, so the security impact of this vulnerability is low.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-v4w5-p2hg-8fh6Urllib3 Incorrect Certificate Validation2022-05-17ghsa · osvUS
Versions 1.17 and 1.18 of the Python urllib3 library suffer from a vulnerability that can cause them, in certain configurations, to not correctly validate TLS certificates. This places users of the library with those configurations at risk of man-in-the-middle and information leakage attacks. This vulnerability affects users using versions 1.17 and 1.18 of the urllib3 library, who are using the optional PyOpenSSL support for TLS instead of the regular standard library TLS backend, and who are using OpenSSL 1.1.0 via PyOpenSSL. This is an extremely uncommon configuration, so the security impact of this vulnerability is low.
- PYSEC-2017-982017-01-11vendor · osvUS
Versions 1.17 and 1.18 of the Python urllib3 library suffer from a vulnerability that can cause them, in certain configurations, to not correctly validate TLS certificates. This places users of the library with those configurations at risk of man-in-the-middle and information leakage attacks. This vulnerability affects users using versions 1.17 and 1.18 of the urllib3 library, who are using the optional PyOpenSSL support for TLS instead of the regular standard library TLS backend, and who are using OpenSSL 1.1.0 via PyOpenSSL. This is an extremely uncommon configuration, so the security impact of this vulnerability is low.
also known as (6)
Other names and identifiers for this entity.
sources
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references (9)
External citations — patches, advisories, analysis.
- http://www.openwall.com/lists/oss-security/2016/10/27/6cnnvd
- http://www.securityfocus.com/bid/93941cnnvd
- https://pypi.python.org/pypi/urllib3Patchcnnvd
- https://vigilance.fr/vulnerability/Python-urllib3-information-disclosure-via-TLS-Certificate-Validation-28481cnnvd
- https://www.auscert.org.au/bulletins/ESB-2022.0696cnnvd
- http://www.openwall.com/lists/oss-security/2016/10/27/6enisa_euvd
- http://www.securityfocus.com/bid/93941enisa_euvd
- http://www.openwall.com/lists/oss-security/2016/10/27/6Mailing ListMitigationnvd
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