Description
The urllib3 library 1.26.x before 1.26.4 for Python omits SSL certificate validation in some cases involving HTTPS to HTTPS proxies. The initial connection to the HTTPS proxy (if an SSLContext isn't given via proxy_config) doesn't verify the hostname of the certificate. This means certificates for different servers that still validate properly with the default urllib3 SSLContext will be silently accepted.
Metrics
CVSS 3.1 6.5/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| n/a | n/a | n/a |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | >= V3.1.0, < V3.1.5 |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | >= V3.1.0, < V3.1.5 |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | >= V3.1.0, < V3.1.5 |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | >= V3.1.0, < V3.1.5 |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | >= V3.1.0, < V3.1.5 |
References
- https://github.com/urllib3/urllib3/commit/8d65ea1ecf6e2cdc27d42124e587c1b83a3118b0Patch, Third Party Advisory
- https://github.com/urllib3/urllib3/commits/mainPatch, Third Party Advisory
- https://github.com/urllib3/urllib3/security/advisories/GHSA-5phf-pp7p-vc2rMitigation, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S65ZQVZ2ODGB52IC7VJDBUK4M5INCXL/
- https://pypi.org/project/urllib3/1.26.4/Third Party Advisory
- https://security.gentoo.org/glsa/202107-36Third Party Advisory
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20240621-0007/
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory
- https://github.com/urllib3/urllib3/commit/8d65ea1ecf6e2cdc27d42124e587c1b83a3118b0Patch, Third Party Advisory
- https://github.com/urllib3/urllib3/commits/mainPatch, Third Party Advisory
- https://github.com/urllib3/urllib3/security/advisories/GHSA-5phf-pp7p-vc2rMitigation, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S65ZQVZ2ODGB52IC7VJDBUK4M5INCXL/
- https://pypi.org/project/urllib3/1.26.4/Third Party Advisory
- https://security.gentoo.org/glsa/202107-36Third Party Advisory
- https://security.gentoo.org/glsa/202305-02
- https://security.netapp.com/advisory/ntap-20240621-0007/
- https://www.oracle.com/security-alerts/cpuoct2021.htmlPatch, Third Party Advisory
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
Timeline
- Published
- Mar 15, 2021
- Last modified
- Oct 14, 2026
- NVD status
- Modified