From accff72ecc2f6cf5a76d9570198a93ac7c90270e Mon Sep 17 00:00:00 2001
From: Quentin Pradet <quentin.pradet@gmail.com>
Date: Mon, 17 Jun 2024 11:09:06 +0400
Subject: [PATCH] Merge pull request from GHSA-34jh-p97f-mpxf

* Strip Proxy-Authorization header on redirects

Conflict:Files test/test_retry.py and test/with_dummyserver/test_poolmanager.py do not
exist. Therefore, no test case is involved.
Reference:https://github.com/urllib3/urllib3/commit/accff72ecc2f6cf5a76d9570198a93ac7c90270e

---
 src/pip/_vendor/urllib3/util/retry.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/pip/_vendor/urllib3/util/retry.py b/src/pip/_vendor/urllib3/util/retry.py
index 545e876..b4a2d3d 100644
--- a/src/pip/_vendor/urllib3/util/retry.py
+++ b/src/pip/_vendor/urllib3/util/retry.py
@@ -154,7 +154,9 @@ class Retry(object):
 
     RETRY_AFTER_STATUS_CODES = frozenset([413, 429, 503])
 
-    DEFAULT_REDIRECT_HEADERS_BLACKLIST = frozenset(["Cookie","Authorization"])
+    DEFAULT_REDIRECT_HEADERS_BLACKLIST = frozenset(
+        ["Cookie", "Authorization", "Proxy-Authorization"]
+    )
 
     #: Maximum backoff time.
     BACKOFF_MAX = 120
-- 
