diff --git a/src/Monolog/Formatter/RedactingFormatter.php b/src/Monolog/Formatter/RedactingFormatter.php
index ed766d2..d97a66a 100644
--- a/src/Monolog/Formatter/RedactingFormatter.php
+++ b/src/Monolog/Formatter/RedactingFormatter.php
@@ -203,8 +203,9 @@ final class RedactingFormatter implements WrappingFormatterInterface
         if (\is_array($data)) {
             foreach ($data as $key => $value) {
                 if (\is_string($key) && \in_array(strtolower($key), $this->sensitiveKeys, true)) {
-                    // no need to recurse, the whole value is masked in the record anyway
-                    $this->addSecret($value, $secrets);
+                    // the value is masked in the record, but a nested array's leaves can still
+                    // leak elsewhere (e.g. json-encoded by PsrLogMessageProcessor)
+                    $this->collectSensitiveValue($value, $secrets, $depth + 1);
 
                     continue;
                 }
@@ -239,6 +240,28 @@ final class RedactingFormatter implements WrappingFormatterInterface
         }
     }
 
+    /**
+     * Collects every string leaf nested inside a value under a sensitive key.
+     *
+     * @param list<string> $secrets
+     */
+    private function collectSensitiveValue(mixed $value, array &$secrets, int $depth): void
+    {
+        if ($depth > self::MAX_DEPTH) {
+            return;
+        }
+
+        if (\is_array($value)) {
+            foreach ($value as $item) {
+                $this->collectSensitiveValue($item, $secrets, $depth + 1);
+            }
+
+            return;
+        }
+
+        $this->addSecret($value, $secrets);
+    }
+
     /**
      * Reflects the properties of an object matching a #[SensitiveParameter] constructor parameter
      *
diff --git a/tests/Monolog/Formatter/RedactingFormatterTest.php b/tests/Monolog/Formatter/RedactingFormatterTest.php
index ef4349c..f8c365a 100644
--- a/tests/Monolog/Formatter/RedactingFormatterTest.php
+++ b/tests/Monolog/Formatter/RedactingFormatterTest.php
@@ -243,6 +243,22 @@ class RedactingFormatterTest extends MonologTestCase
         $this->assertStringContainsString('calling api with [REDACTED]', $output);
     }
 
+    public function testRedactsSecretNestedInAnArrayValueAlreadyInterpolatedIntoTheMessage()
+    {
+        // PsrLogMessageProcessor json-encodes array context into the message, so a
+        // secret nested under a sensitive key leaks before this formatter runs.
+        $formatter = new RedactingFormatter(new LineFormatter('%message% %context%', 'Y-m-d'));
+        $processor = new PsrLogMessageProcessor();
+
+        $output = $formatter->format($processor($this->getRecord(
+            message: 'password reset payload: {password}',
+            context: ['password' => ['new' => 'tok-supersecret-value']],
+        )));
+
+        $this->assertStringNotContainsString('tok-supersecret-value', $output);
+        $this->assertStringContainsString('[REDACTED]', $output);
+    }
+
     public function testRedactsSecretEmbeddedInAnExceptionMessage()
     {
         $formatter = new RedactingFormatter(new JsonFormatter());