Bug 2543255 (CVE-2026-97687) - CVE-2026-97687 urllib3: urllib3: Traffic interception via HTTPS proxy TLS configuration override
Summary: CVE-2026-97687 urllib3: urllib3: Traffic interception via HTTPS proxy TLS con...
Keywords:
Status: NEW
Alias: CVE-2026-97687
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-09-29 15:54 UTC by OSIDB Bzimport
Modified: 2026-11-11 01:59 UTC (History)
153 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:

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Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2026:92373 0 None None None 2026-10-29 13:14:04 UTC
Red Hat Product Errata RHSA-2026:84577 0 None None None 2026-10-19 01:56:42 UTC
Red Hat Product Errata RHSA-2026:84578 0 None None None 2026-10-19 01:53:28 UTC
Red Hat Product Errata RHSA-2026:85929 0 None None None 2026-10-20 12:58:38 UTC
Red Hat Product Errata RHSA-2026:85930 0 None None None 2026-10-20 12:26:15 UTC
Red Hat Product Errata RHSA-2026:90494 0 None None None 2026-10-26 21:26:46 UTC
Red Hat Product Errata RHSA-2026:92474 0 None None None 2026-10-29 16:24:20 UTC
Red Hat Product Errata RHSA-2026:95655 0 None None None 2026-11-05 19:44:55 UTC
Red Hat Product Errata RHSA-2026:95656 0 None None None 2026-11-05 19:40:32 UTC
Red Hat Product Errata RHSA-2026:95657 0 None None None 2026-11-05 19:44:36 UTC
Red Hat Product Errata RHSA-2026:98096 0 None None None 2026-11-11 01:16:02 UTC
Red Hat Product Errata RHSA-2026:98097 0 None None None 2026-11-11 01:45:04 UTC
Red Hat Product Errata RHSA-2026:98098 0 None None None 2026-11-11 01:45:24 UTC
Red Hat Product Errata RHSA-2026:98122 0 None None None 2026-11-11 01:59:03 UTC
Red Hat Product Errata RHSA-2026:98125 0 None None None 2026-11-11 01:51:56 UTC
Red Hat Product Errata RHSA-2026:98126 0 None None None 2026-11-11 01:57:49 UTC

Description OSIDB Bzimport 2026-09-29 15:54:30 UTC 
urllib3 is an HTTP client library for Python. From 1.26.0 until 2.8.0, the proxy_ssl_context, proxy_assert_hostname, proxy_assert_fingerprint, ssl_context, cert_reqs, verify_mode, use_forwarding_for_https=True, and CERT_NONE configuration paths fail to remain separated because target-server TLS settings are incorrectly applied to the HTTPS proxy connection. The trigger is that an application uses an HTTPS proxy and configures target-server TLS settings that must remain separate from the proxy TLS handshake, including HTTPS forwarding with target-specific identity or credentials. Applying cert_reqs=CERT_NONE can overwrite proxy_ssl_context.verify_mode in place, and the mutation persists so later connections reusing the same context may connect to the HTTPS proxy without certificate verification. The attack mechanism is that an attacker intercepts and impersonates the HTTPS proxy after the effective proxy policy accepts the attacker's certificate. The impact is that the attacker can observe or modify forwarded traffic or receive a target TLS client certificate, while CONNECT tunneling still preserves the separate end-to-end target TLS connection. This issue is fixed in version 2.8.0.
Comment 1 Jon Orris 2026-10-19 01:53:26 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:84578 https://access.redhat.com/errata/RHSA-2026:84578
Comment 2 Jon Orris 2026-10-19 01:56:38 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:84577 https://access.redhat.com/errata/RHSA-2026:84577
Comment 3 Jon Orris 2026-10-20 12:26:14 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:85930 https://access.redhat.com/errata/RHSA-2026:85930
Comment 4 Jon Orris 2026-10-20 12:58:36 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:85929 https://access.redhat.com/errata/RHSA-2026:85929
Comment 5 Jon Orris 2026-10-26 21:26:45 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:90494 https://access.redhat.com/errata/RHSA-2026:90494
Comment 7 Jon Orris 2026-10-29 16:24:12 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:92474 https://access.redhat.com/errata/RHSA-2026:92474
Comment 10 Jon Orris 2026-11-05 19:40:23 UTC 
This issue has been addressed in the following products:

  Red Hat Satellite 6.17 for RHEL 9

Via RHSA-2026:95656 https://access.redhat.com/errata/RHSA-2026:95656
Comment 11 Jon Orris 2026-11-05 19:44:28 UTC 
This issue has been addressed in the following products:

  Red Hat Satellite 6.18 for RHEL 9

Via RHSA-2026:95657 https://access.redhat.com/errata/RHSA-2026:95657
Comment 12 Jon Orris 2026-11-05 19:44:46 UTC 
This issue has been addressed in the following products:

  Red Hat Satellite 6.16 for RHEL 8
  Red Hat Satellite 6.16 for RHEL 9

Via RHSA-2026:95655 https://access.redhat.com/errata/RHSA-2026:95655
Comment 13 errata-xmlrpc 2026-11-11 01:15:52 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:98096 https://access.redhat.com/errata/RHSA-2026:98096
Comment 14 errata-xmlrpc 2026-11-11 01:44:53 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:98097 https://access.redhat.com/errata/RHSA-2026:98097
Comment 15 errata-xmlrpc 2026-11-11 01:45:15 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:98098 https://access.redhat.com/errata/RHSA-2026:98098
Comment 16 errata-xmlrpc 2026-11-11 01:51:47 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Via RHSA-2026:98125 https://access.redhat.com/errata/RHSA-2026:98125
Comment 17 errata-xmlrpc 2026-11-11 01:57:39 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:98126 https://access.redhat.com/errata/RHSA-2026:98126
Comment 18 errata-xmlrpc 2026-11-11 01:58:53 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:98122 https://access.redhat.com/errata/RHSA-2026:98122
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