CVE-2023-32681

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.

Impact

Since Requests v2.3.0, Requests has been vulnerable to potentially leaking Proxy-Authorization headers to destination servers, specifically during redirects to an HTTPS origin. This is a product of how rebuild_proxies is used to recompute and reattach the Proxy-Authorization header to requests when redirected. Note this behavior has only been observed to affect proxied requests when credentials are supplied in the URL user information component (e.g. https://username:password@proxy:8080).

Current vulnerable behavior(s):

1. HTTP → HTTPS: leak
2. HTTPS → HTTP: no leak
3. HTTPS → HTTPS: leak
4. HTTP → HTTP: no leak

For HTTP connections sent through the proxy, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into further tunneled requests. This results in Requests forwarding the header to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate those credentials.

The reason this currently works for HTTPS connections in Requests is the Proxy-Authorization header is also handled by urllib3 with our usage of the ProxyManager in adapters.py with proxy_manager_for. This will compute the required proxy headers in proxy_headers and pass them to the Proxy Manager, avoiding attaching them directly to the Request object. This will be our preferred option going forward for default usage.

Patches

Starting in Requests v2.31.0, Requests will no longer attach this header to redirects with an HTTPS destination. This should have no negative impacts on the default behavior of the library as the proxy credentials are already properly being handled by urllib3's ProxyManager.

For users with custom adapters, this may be potentially breaking if you were already working around this behavior. The previous functionality of rebuild_proxies doesn't make sense in any case, so we would encourage any users impacted to migrate any handling of Proxy-Authorization directly into their custom adapter.

Workarounds

For users who are not able to update Requests immediately, there is one potential workaround.

You may disable redirects by setting allow_redirects to False on all calls through Requests top-level APIs. Note that if you're currently relying on redirect behaviors, you will need to capture the 3xx response codes and ensure a new request is made to the redirect destination.

import requests
r = requests.get('http://github.com/', allow_redirects=False)

Credits

This vulnerability was discovered and disclosed by the following individuals.

Dennis Brinkrolf, Haxolot (https://haxolot.com/) Tobias Funke, ([email protected])

Requests is an HTTP library, written in Python, as an alternative to Python's builtin urllib2 which requires work (even method overrides) to perform basic tasks. Features of Requests: - GET, HEAD, POST, PUT, DELETE Requests: + HTTP Header Request Attachment. + Data/Params Request Attachment. + Multipart File Uploads. + CookieJar Support. + Redirection History. + Redirection Recursion Urllib Fix. + Automatic Decompression of GZipped Content. + Unicode URL Support.- Authentication: + URL + HTTP Auth Registry.

Security Fix(es):

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.

(CVE-2023-32681)

pip is the package installer for Python. You can use pip to install packages from the Python Package Index and other indexes. %global bashcompdir %(b=$(pkg-config --variable=completionsdir bash-completion 2>/dev/null); echo ${b:-/bash_completion.d}) Name: python-pip Version: 23.3.1 Release: 5 Summary: A tool for installing and managing Python packages License: MIT and Python and ASL 2.0 and BSD and ISC and LGPLv2 and MPLv2.0 and (ASL 2.0 or BSD) URL: http://www.pip-installer.org Source0: Source1: pip.loongarch.conf BuildArch: noarch Patch1: remove-existing-dist-only-if-path-conflicts. Patch6000: dummy-certifi.patch Patch6001: backport-CVE-2023-45803-Made-body-stripped-from-HTTP-requests.patch Patch6002: backport-CVE-2024-37891-Strip-Proxy-Authorization-header-on-redirects.patch Patch6003: backport-CVE-2024-47081.patch Patch6004: backport-CVE-2025-50181.patch

Security Fix(es):

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.(CVE-2023-32681)

pip is the package installer for Python. You can use pip to install packages from the Python Package Index and other indexes. %global bashcompdir %(b=$(pkg-config --variable=completionsdir bash-completion 2>/dev/null); echo ${b:-/bash_completion.d}) Name: python-pip Version: 23.3.1 Release: 5 Summary: A tool for installing and managing Python packages License: MIT and Python and ASL 2.0 and BSD and ISC and LGPLv2 and MPLv2.0 and (ASL 2.0 or BSD) URL: http://www.pip-installer.org Source0: Source1: pip.loongarch.conf BuildArch: noarch Patch1: remove-existing-dist-only-if-path-conflicts. Patch6000: dummy-certifi.patch Patch6001: backport-CVE-2023-45803-Made-body-stripped-from-HTTP-requests.patch Patch6002: backport-CVE-2024-37891-Strip-Proxy-Authorization-header-on-redirects.patch Patch6003: backport-CVE-2024-47081.patch Patch6004: backport-CVE-2025-50181.patch

Security Fix(es):

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.(CVE-2023-32681)

pip is the package installer for Python. You can use pip to install packages from the Python Package Index and other indexes. %global bashcompdir %(b=$(pkg-config --variable=completionsdir bash-completion 2>/dev/null); echo ${b:-/bash_completion.d}) Name: python-pip Version: 23.3.1 Release: 5 Summary: A tool for installing and managing Python packages License: MIT and Python and ASL 2.0 and BSD and ISC and LGPLv2 and MPLv2.0 and (ASL 2.0 or BSD) URL: http://www.pip-installer.org Source0: Source1: pip.loongarch.conf BuildArch: noarch Patch1: remove-existing-dist-only-if-path-conflicts. Patch6000: dummy-certifi.patch Patch6001: backport-CVE-2023-45803-Made-body-stripped-from-HTTP-requests.patch Patch6002: backport-CVE-2024-37891-Strip-Proxy-Authorization-header-on-redirects.patch Patch6003: backport-CVE-2024-47081.patch Patch6004: backport-CVE-2025-50181.patch

Security Fix(es):

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.(CVE-2023-32681)

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.

Security Fix(es):

• python: tarfile module directory traversal (CVE-2007-4559)

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 8.9 Release Notes linked from the References section.

Python is an interpreted, interactive, object-oriented programming language that supports modules, classes, exceptions, high-level dynamic data types, and dynamic typing. The python27 packages provide a stable release of Python 2.7 with a number of additional utilities and database connectors for MySQL and PostgreSQL.

Security Fix(es):

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 8.9 Release Notes linked from the References section.

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.

Security Fix(es):

• python: tarfile module directory traversal (CVE-2007-4559)

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 8.9 Release Notes linked from the References section.

Root has patched CVE-2023-32681 in the rootio-requests package for Root:PyPI. Multiple fixed versions available.

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.

The python-requests package contains a library designed to make HTTP requests easy for developers.

Security Fix(es):

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

The python-requests package contains a library designed to make HTTP requests easy for developers.

Security Fix(es):

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.

Security Fix(es):

• python: tarfile module directory traversal (CVE-2007-4559)
• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

Python is an interpreted, interactive, object-oriented programming language that supports modules, classes, exceptions, high-level dynamic data types, and dynamic typing. The python27 packages provide a stable release of Python 2.7 with a number of additional utilities and database connectors for MySQL and PostgreSQL.

Security Fix(es):

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.

Security Fix(es):

• python: tarfile module directory traversal (CVE-2007-4559)
• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

TuxCare rebuilt requests to address 1 CVE. Fixed in 2.25.1.post1+tuxcare.

TuxCare rebuilt requests to address 1 CVE. Fixed in 2.30.0.post1+tuxcare.

TuxCare rebuilt requests to address 3 CVEs. Fixed in 2.25.1.post3+tuxcare.

TuxCare rebuilt requests to address 3 CVEs. Fixed in 2.30.0.post3+tuxcare.

Forwarding proxy credentials to the destination server unintentionally (CVE-2023-32681)

These are all security issues fixed in the python310-requests-2.31.0-1.2 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the oci-cli-3.54.1-1.1 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the python313-requests-2.34.2-1.2 package on the GA media of openSUSE Tumbleweed.

Requests is a HTTP library. Since Requests 2.3.0, Requests has been leaking Proxy-Authorization headers to destination servers when redirected to an HTTPS endpoint. This is a product of how we use rebuild_proxies to reattach the Proxy-Authorization header to requests. For HTTP connections sent through the tunnel, the proxy will identify the header in the request itself and remove it prior to forwarding to the destination server. However when sent over HTTPS, the Proxy-Authorization header must be sent in the CONNECT request as the proxy has no visibility into the tunneled request. This results in Requests forwarding proxy credentials to the destination server unintentionally, allowing a malicious actor to potentially exfiltrate sensitive information. This issue has been patched in version 2.31.0.

The python-requests package contains a library designed to make HTTP requests easy for developers.

Security Fix(es):

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Rocky Enterprise Software Foundation Satellite is a systems management tool for Linux-based infrastructure. It allows for provisioning, remote management, and monitoring of multiple Linux deployments with a single centralized tool.

Security Fix(es):

• golang: net/http, x/net/http2: rapid stream resets can cause excessive work (CVE-2023-44487) (CVE-2023-39325)

• HTTP/2: Multiple HTTP/2 enabled web servers are vulnerable to a DDoS attack (Rapid Reset Attack) (CVE-2023-44487)

• GitPython: Insecure non-multi options in clone and clone_from is not blocked (CVE-2023-40267)

• kubeclient: kubeconfig parsing error can lead to MITM attacks (CVE-2022-0759)

• foreman: OS command injection via ct_command and fcct_command (CVE-2022-3874)

• ruby-git: code injection vulnerability (CVE-2022-46648)

• ruby-git: code injection vulnerability (CVE-2022-47318)

• Foreman: Arbitrary code execution through templates (CVE-2023-0118)

• rubygem-activerecord: SQL Injection (CVE-2023-22794)

• openssl: c_rehash script allows command injection (CVE-2022-1292)

• openssl: the c_rehash script allows command injection (CVE-2022-2068)

• Pulp:Tokens stored in plaintext (CVE-2022-3644)

• satellite: Blind SSRF via Referer header (CVE-2022-4130)

• python-future: remote attackers can cause denial of service via crafted Set-Cookie header from malicious web server (CVE-2022-40899)

• golang: net/http: excessive memory growth in a Go server accepting HTTP/2 requests (CVE-2022-41717)

• rubygem-activerecord: Denial of Service (CVE-2022-44566)

• rubygem-rack: denial of service in Content-Disposition parsing (CVE-2022-44570)

• rubygem-rack: denial of service in Content-Disposition parsing (CVE-2022-44571)

• rubygem-rack: denial of service in Content-Disposition parsing (CVE-2022-44572)

• Foreman: Stored cross-site scripting in host tab (CVE-2023-0119)

• puppet: Puppet Server ReDoS (CVE-2023-1894)

• rubygem-actionpack: Denial of Service in Action Dispatch (CVE-2023-22792)

• rubygem-actionpack: Denial of Service in Action Dispatch (CVE-2023-22795)

• rubygem-activesupport: Regular Expression Denial of Service (CVE-2023-22796)

• rubygem-globalid: ReDoS vulnerability (CVE-2023-22799)

• rubygem-rack: Denial of service in Multipart MIME parsing (CVE-2023-27530)

• rubygem-rack: denial of service in header parsing (CVE-2023-27539)

• golang: net/http: insufficient sanitization of Host header (CVE-2023-29406)

• sqlparse: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service) (CVE-2023-30608)

• python-django: Potential bypass of validation when uploading multiple files using one form field (CVE-2023-31047)

• python-requests: Unintended leak of Proxy-Authorization header (CVE-2023-32681)

• python-django: Potential regular expression denial of service vulnerability in EmailValidator/URLValidator (CVE-2023-36053)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

This update also fixes several bugs and adds various enhancements. Documentation for these changes is available from the Release Notes document linked to in the References section.

This update for python-requests fixes the following issues:

• CVE-2023-32681: Fixed unintended leak of Proxy-Authorization header (bsc#1211674).

This update for python-requests fixes the following issues:

• CVE-2023-32681: Fixed unintended leak of Proxy-Authorization header (bsc#1211674).

This update for python-requests fixes the following issues:

• CVE-2023-32681: Fixed unintended leak of Proxy-Authorization header (bsc#1211674).

This update for python3-requests fixes the following issues:

• CVE-2023-32681: Fixed unintended leak of Proxy-Authorization header (bsc#1211674).

This update for python-requests fixes the following issues:

• CVE-2023-32681: fixed unintended leak of Proxy-Authorization header (bsc#1211674).

This update for python-requests fixes the following issues:

• CVE-2023-32681: Fixed unintended leak of Proxy-Authorization header (bsc#1211674).

Dennis Brinkrolf and Tobias Funke discovered that Requests incorrectly leaked Proxy-Authorization headers. A remote attacker could possibly use this issue to obtain sensitive information.

USN-6155-1 fixed a vulnerability in Requests. This update provides the corresponding update for Ubuntu 16.04 ESM and 18.04 ESM.

Original advisory details:

Dennis Brinkrolf and Tobias Funke discovered that Requests incorrectly leaked Proxy-Authorization headers. A remote attacker could possibly use this issue to obtain sensitive information.

Dennis Brinkrolf and Tobias Funke discovered that Requests did not correctly handle certain HTTP headers. A remote attacker could possibly use this issue to leak sensitive information. This issue only affected Ubuntu 14.04 LTS. (CVE-2023-32681)

Juho Forsén discovered that Requests did not correctly parse URLs. A remote attacker could possibly use this issue to leak sensitive information. (CVE-2024-47081)

Dennis Brinkrolf and Tobias Funke discovered that Requests incorrectly leaked Proxy-Authorization headers. A remote attacker could possibly use this issue to obtain sensitive information. This update addresses the issue in the Requests module bundled into pip in Ubuntu 22.04 LTS. (CVE-2023-32681)

It was discovered that urllib3 didn't strip HTTP body on status code 303 redirects under certain circumstances. A remote attacker could possibly use this issue to obtain sensitive information. This update addresses the issue in the urllib3 module bundled into pip in Ubuntu 24.04 LTS. (CVE-2023-45803)

Guido Vranken discovered that idna did not properly manage certain inputs, which could lead to significant resource consumption. An attacker could possibly use this issue to cause a denial of service. This update addresses the issue in the idna module bundled into pip in Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2024-3651)

Juho Forsén discovered that Requests did not correctly parse URLs. A remote attacker could possibly use this issue to leak sensitive information. This update addresses the issue in the Requests module bundled into pip in Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 25.04. (CVE-2024-47081)