diff --git a/src/Composer/Advisory/PartialSecurityAdvisory.php b/src/Composer/Advisory/PartialSecurityAdvisory.php
index c5234591b..28dbdc4f4 100644
--- a/src/Composer/Advisory/PartialSecurityAdvisory.php
+++ b/src/Composer/Advisory/PartialSecurityAdvisory.php
@@ -14,8 +14,9 @@ namespace Composer\Advisory;
 
 use Composer\Semver\Constraint\ConstraintInterface;
 use Composer\Semver\VersionParser;
+use JsonSerializable;
 
-class PartialSecurityAdvisory
+class PartialSecurityAdvisory implements JsonSerializable
 {
     /**
      * @var string
@@ -55,4 +56,16 @@ class PartialSecurityAdvisory
         $this->packageName = $packageName;
         $this->affectedVersions = $affectedVersions;
     }
+
+    /**
+     * @return mixed
+     */
+    #[\ReturnTypeWillChange]
+    public function jsonSerialize()
+    {
+        $data = (array) $this;
+        $data['affectedVersions'] = $data['affectedVersions']->getPrettyString();
+
+        return $data;
+    }
 }
diff --git a/src/Composer/Advisory/SecurityAdvisory.php b/src/Composer/Advisory/SecurityAdvisory.php
index a574ed4b0..8fdf4dd55 100644
--- a/src/Composer/Advisory/SecurityAdvisory.php
+++ b/src/Composer/Advisory/SecurityAdvisory.php
@@ -61,4 +61,16 @@ class SecurityAdvisory extends PartialSecurityAdvisory
         $this->cve = $cve;
         $this->link = $link;
     }
+
+    /**
+     * @return mixed
+     */
+    #[\ReturnTypeWillChange]
+    public function jsonSerialize()
+    {
+        $data = parent::jsonSerialize();
+        $data['reportedAt'] = $data['reportedAt']->format(DATE_RFC3339);
+
+        return $data;
+    }
 }