diff --git a/server/app/common/service/DifyChatService.php b/server/app/common/service/DifyChatService.php
index 745e7b5b7..a60cc2b76 100644
--- a/server/app/common/service/DifyChatService.php
+++ b/server/app/common/service/DifyChatService.php
@@ -726,6 +726,21 @@ class DifyChatService
         ];
     }
 
+    /**
+     * libcurl 7.32+ exposes CURLOPT_XFERINFOFUNCTION, while CentOS/RHEL 7 commonly
+     * ships libcurl 7.29 with only CURLOPT_PROGRESSFUNCTION. Resolve the option
+     * by name so loading this class never evaluates an undefined PHP constant.
+     */
+    private static function curlProgressOption(): ?int
+    {
+        foreach (['CURLOPT_XFERINFOFUNCTION', 'CURLOPT_PROGRESSFUNCTION'] as $name) {
+            if (defined($name)) {
+                return (int) constant($name);
+            }
+        }
+        return null;
+    }
+
     /**
      * @param array<string,mixed> $payload
      * @param callable(string):mixed $onDelta
@@ -783,7 +798,7 @@ class DifyChatService
             self::consumeStreamBytes($protocol, $buffer, $chunk, $state, $onDelta);
             return $state['callback_error'] ? 0 : strlen($chunk);
         };
-        $progress = static function () use (&$state, $shouldAbort): int {
+        $progress = static function (...$unused) use (&$state, $shouldAbort): int {
             if ($shouldAbort !== null && $shouldAbort()) {
                 $state['client_aborted'] = true;
                 return 1;
@@ -791,7 +806,7 @@ class DifyChatService
             return 0;
         };
 
-        curl_setopt_array($ch, [
+        $curlOptions = [
             CURLOPT_URL => $url,
             CURLOPT_POST => true,
             CURLOPT_POSTFIELDS => $body,
@@ -807,9 +822,13 @@ class DifyChatService
             ],
             CURLOPT_HEADERFUNCTION => $header,
             CURLOPT_WRITEFUNCTION => $write,
-            CURLOPT_NOPROGRESS => false,
-            CURLOPT_XFERINFOFUNCTION => $progress,
-        ]);
+        ];
+        $progressOption = self::curlProgressOption();
+        if ($progressOption !== null) {
+            $curlOptions[CURLOPT_NOPROGRESS] = false;
+            $curlOptions[$progressOption] = $progress;
+        }
+        curl_setopt_array($ch, $curlOptions);
 
         curl_exec($ch);
         $errno = curl_errno($ch);
diff --git a/server/tests/DifyChatStreamContractTest.php b/server/tests/DifyChatStreamContractTest.php
index 22257344a..fe05c63c1 100644
--- a/server/tests/DifyChatStreamContractTest.php
+++ b/server/tests/DifyChatStreamContractTest.php
@@ -95,6 +95,25 @@ $explicitOpenAi = callDifyStreamPrivate('buildRequestSpecs', [
 difyStreamExpect(count($explicitDify) === 1 && $explicitDify[0]['protocol'] === 'dify', 'explicit Dify endpoint never changes protocol');
 difyStreamExpect(count($explicitOpenAi) === 1 && $explicitOpenAi[0]['protocol'] === 'openai', 'explicit OpenAI endpoint never changes protocol');
 
+$progressOption = callDifyStreamPrivate('curlProgressOption', []);
+$expectedProgressOption = null;
+foreach (['CURLOPT_XFERINFOFUNCTION', 'CURLOPT_PROGRESSFUNCTION'] as $optionName) {
+    if (defined($optionName)) {
+        $expectedProgressOption = (int) constant($optionName);
+        break;
+    }
+}
+difyStreamExpect(
+    $progressOption === $expectedProgressOption,
+    'stream cancellation selects the newest cURL progress callback available at runtime'
+);
+$serviceSource = file_get_contents(dirname(__DIR__) . '/app/common/service/DifyChatService.php');
+difyStreamExpect(
+    is_string($serviceSource)
+        && str_contains($serviceSource, "'CURLOPT_XFERINFOFUNCTION', 'CURLOPT_PROGRESSFUNCTION'"),
+    'stream cancellation retains the libcurl 7.29 progress callback fallback'
+);
+
 $retryableStream = [
     'errno' => 0,
     'http_code' => 200,