diff --git a/src/Core/CHANGELOG.md b/src/Core/CHANGELOG.md
index d46df2954..8dddfb3d1 100644
--- a/src/Core/CHANGELOG.md
+++ b/src/Core/CHANGELOG.md
@@ -19,6 +19,7 @@
 ### Fixed
 
 - Buffer the response in temporary file to avoid issues when stream is used by another request's body
+- SignerV4: Fix signing request during DST change
 
 
 ## 1.27.1
diff --git a/src/Core/src/Signer/SignerV4.php b/src/Core/src/Signer/SignerV4.php
index 2d371de2a..b82d37d4d 100644
--- a/src/Core/src/Signer/SignerV4.php
+++ b/src/Core/src/Signer/SignerV4.php
@@ -62,7 +62,7 @@ public function __construct(string $scopeName, string $region)
 
     public function presign(Request $request, Credentials $credentials, RequestContext $context): void
     {
-        $now = $context->getCurrentDate() ?? new \DateTimeImmutable();
+        $now = $context->getCurrentDate() ?? new \DateTimeImmutable('now', new \DateTimeZone('UTC'));
 
         // Signer date have to be UTC https://docs.aws.amazon.com/general/latest/gr/sigv4-date-handling.html
         $now = $now->setTimezone(new \DateTimeZone('UTC'));
@@ -73,7 +73,7 @@ public function presign(Request $request, Credentials $credentials, RequestConte
 
     public function sign(Request $request, Credentials $credentials, RequestContext $context): void
     {
-        $now = $context->getCurrentDate() ?? new \DateTimeImmutable();
+        $now = $context->getCurrentDate() ?? new \DateTimeImmutable('now', new \DateTimeZone('UTC'));
 
         // Signer date have to be UTC https://docs.aws.amazon.com/general/latest/gr/sigv4-date-handling.html
         $now = $now->setTimezone(new \DateTimeZone('UTC'));