CVE-2026-55220

Pimcore is an Open Source Data & Experience Management Platform. Prior to 11.5.19, 12.3.10, and 2026.1.6, Pimcore\Model\DataObject\ClassDefinition\Data\Hotspotimage::getDataFromResource() in models/DataObject/ClassDefinition/Data/Hotspotimage.php passes the field __hotspots object-store column to Pimcore\Tool\Serialize::unserialize() without an allowed-classes restriction after JSON decoding fails. An attacker with a separate capability to write crafted PHP serialized bytes into that column can instantiate available classes and trigger magic methods when an affected DataObject is loaded, which can produce arbitrary file writes or code execution through bundled gadget chains. The related ImageGallery, Block, and Video callers use the same fallback pattern, but the identified June fix changes the Hotspotimage caller only. This issue is fixed for Hotspotimage in versions 11.5.19, 12.3.10, and 2026.1.6.

Pimcore is an Open Source Data & Experience Management Platform. Prior to 11.5.19, 12.3.10, and 2026.1.6, Pimcore\Model\DataObject\ClassDefinition\Data\Hotspotimage::getDataFromResource() in models/DataObject/ClassDefinition/Data/Hotspotimage.php passes the field __hotspots object-store column to Pimcore\Tool\Serialize::unserialize() without an allowed-classes restriction after JSON decoding fails. An attacker with a separate capability to write crafted PHP serialized bytes into that column can instantiate available classes and trigger magic methods when an affected DataObject is loaded, which can produce arbitrary file writes or code execution through bundled gadget chains. The related ImageGallery, Block, and Video callers use the same fallback pattern, but the identified June fix changes the Hotspotimage caller only. This issue is fixed for Hotspotimage in versions 11.5.19, 12.3.10, and 2026.1.6.

Summary

Pimcore\Model\DataObject\ClassDefinition\Data\Hotspotimage::getDataFromResource() deserializes the *__hotspots object-store column through the Pimcore\Tool\Serialize::unserialize() wrapper without a class allowlist (the wrapper's $allowedClasses parameter defaults to true, i.e. fully unrestricted). Because the persistence layer always stores this column as PHP-serialize()d bytes, every load of a DataObject that has a Hotspotimage (advanced image) field runs an unrestricted unserialize() over the stored column value. An attacker who can write the *__hotspots store column with crafted serialized bytes achieves PHP Object Injection (CWE-502): arbitrary classes are instantiated and their magic methods (__wakeup/__destruct) execute, which is exploitable for remote code execution via gadget chains present in Pimcore's own bundled dependencies (e.g. guzzlehttp/guzzle).

The same field-data family also affects the sibling marshallers ImageGallery, Block, and Video, which use the identical json_decode(...) ?: Serialize::unserialize(...) fallback over their respective store columns. The root cause is shared: Serialize::unserialize() defaults to an unrestricted class list, and these callers pass no second argument.

Severity

High. Successful exploitation yields PHP Object Injection leading to remote code execution (proven below as arbitrary file write using a gadget from Pimcore's bundled guzzlehttp/guzzle 7.11.0). This is the deserialization leg of an attack: it requires the ability to write the *__hotspots object-store column with attacker-chosen serialized bytes. No class-allowlist defense is present, so any such write is directly weaponizable on the next object load. CVSS-wise this is comparable to other deserialization sinks over attacker-influenceable storage in this codebase.

Affected component

• File: models/DataObject/ClassDefinition/Data/Hotspotimage.php, method getDataFromResource().
• Vulnerable lines (v2026.1.4 / v12.3.8):

  $metaData = $data[$this->getName() . '__hotspots'];
  // check if the data is JSON (backward compatibility)
  $md = json_decode($metaData, true);
  if (!$md) {
      $md = Serialize::unserialize($metaData);   // unrestricted: allowed_classes defaults to true
  } elseif (is_array($md)) {
      $md['hotspots'] = $md;
  }
  

• Root enabler: lib/Tool/Serialize.php

  public static function unserialize(?string $data = null, array|bool $allowedClasses = true): mixed
  {
      if ($data === null || $data === '') { return $data; }
      return unserialize($data, ['allowed_classes' => $allowedClasses]);  // default true = unrestricted
  }
  

• Sibling marshallers with the identical fallback shape: ImageGallery, Block, Video (DataObject\ClassDefinition\Data).
• Package: pimcore/pimcore (Composer).
• Affected versions: all currently maintained releases, including the latest v2026.1.4 and v12.3.8 (verified against deployed v2026.1.4).

Data flow

1. On save, Hotspotimage::getDataForResource() stores the hotspot/marker/crop metadata as Serialize::serialize($metaData) into the <field>__hotspots object-store column — i.e. PHP serialized bytes, not JSON.
2. On load, Hotspotimage::getDataFromResource() reads that column, calls json_decode() (which fails for the serialized format), and therefore falls through to Serialize::unserialize($metaData) with the default unrestricted class list.
3. Serialize::unserialize() invokes unserialize($data, ['allowed_classes' => true]), instantiating any class named in the bytes and triggering its magic methods.
4. The load path is exercised on essentially every object retrieval (admin grid/detail, frontend rendering, Studio/API reads, inheritance walks) for objects whose class declares a Hotspotimage field, with a non-null <field>__image.

The attacker primitive is the ability to place crafted serialized bytes into the <field>__hotspots store column (for…

Pimcore is an Open Source Data & Experience Management Platform. Prior to 11.5.19, 12.3.10, and 2026.1.6, Pimcore\Model\DataObject\ClassDefinition\Data\Hotspotimage::getDataFromResource() in models/DataObject/ClassDefinition/Data/Hotspotimage.php passes the field __hotspots object-store column to Pimcore\Tool\Serialize::unserialize() without an allowed-classes restriction after JSON decoding fails. An attacker with a separate capability to write crafted PHP serialized bytes into that column can instantiate available classes and trigger magic methods when an affected DataObject is loaded, which can produce arbitrary file writes or code execution through bundled gadget chains. The related ImageGallery, Block, and Video callers use the same fallback pattern, but the identified June fix changes the Hotspotimage caller only. This issue is fixed for Hotspotimage in versions 11.5.19, 12.3.10, and 2026.1.6.

Pimcore is an Open Source Data & Experience Management Platform. Prior to 11.5.19, 12.3.10, and 2026.1.6, Pimcore\Model\DataObject\ClassDefinition\Data\Hotspotimage::getDataFromResource() in models/DataObject/ClassDefinition/Data/Hotspotimage.php passes the field __hotspots object-store column to Pimcore\Tool\Serialize::unserialize() without an allowed-classes restriction after JSON decoding fails. An attacker with a separate capability to write crafted PHP serialized bytes into that column can instantiate available classes and trigger magic methods when an affected DataObject is loaded, which can produce arbitrary file writes or code execution through bundled gadget chains. The related ImageGallery, Block, and Video callers use the same fallback pattern, but the identified June fix changes the Hotspotimage caller only. This issue is fixed for Hotspotimage in versions 11.5.19, 12.3.10, and 2026.1.6.

Summary

Pimcore\Model\DataObject\ClassDefinition\Data\Hotspotimage::getDataFromResource() deserializes the *__hotspots object-store column through the Pimcore\Tool\Serialize::unserialize() wrapper without a class allowlist (the wrapper's $allowedClasses parameter defaults to true, i.e. fully unrestricted). Because the persistence layer always stores this column as PHP-serialize()d bytes, every load of a DataObject that has a Hotspotimage (advanced image) field runs an unrestricted unserialize() over the stored column value. An attacker who can write the *__hotspots store column with crafted serialized bytes achieves PHP Object Injection (CWE-502): arbitrary classes are instantiated and their magic methods (__wakeup/__destruct) execute, which is exploitable for remote code execution via gadget chains present in Pimcore's own bundled dependencies (e.g. guzzlehttp/guzzle).

The same field-data family also affects the sibling marshallers ImageGallery, Block, and Video, which use the identical json_decode(...) ?: Serialize::unserialize(...) fallback over their respective store columns. The root cause is shared: Serialize::unserialize() defaults to an unrestricted class list, and these callers pass no second argument.

Severity

High. Successful exploitation yields PHP Object Injection leading to remote code execution (proven below as arbitrary file write using a gadget from Pimcore's bundled guzzlehttp/guzzle 7.11.0). This is the deserialization leg of an attack: it requires the ability to write the *__hotspots object-store column with attacker-chosen serialized bytes. No class-allowlist defense is present, so any such write is directly weaponizable on the next object load. CVSS-wise this is comparable to other deserialization sinks over attacker-influenceable storage in this codebase.

Affected component

• File: models/DataObject/ClassDefinition/Data/Hotspotimage.php, method getDataFromResource().
• Vulnerable lines (v2026.1.4 / v12.3.8):

  $metaData = $data[$this->getName() . '__hotspots'];
  // check if the data is JSON (backward compatibility)
  $md = json_decode($metaData, true);
  if (!$md) {
      $md = Serialize::unserialize($metaData);   // unrestricted: allowed_classes defaults to true
  } elseif (is_array($md)) {
      $md['hotspots'] = $md;
  }
  

• Root enabler: lib/Tool/Serialize.php

  public static function unserialize(?string $data = null, array|bool $allowedClasses = true): mixed
  {
      if ($data === null || $data === '') { return $data; }
      return unserialize($data, ['allowed_classes' => $allowedClasses]);  // default true = unrestricted
  }
  

• Sibling marshallers with the identical fallback shape: ImageGallery, Block, Video (DataObject\ClassDefinition\Data).
• Package: pimcore/pimcore (Composer).
• Affected versions: all currently maintained releases, including the latest v2026.1.4 and v12.3.8 (verified against deployed v2026.1.4).

Data flow

1. On save, Hotspotimage::getDataForResource() stores the hotspot/marker/crop metadata as Serialize::serialize($metaData) into the <field>__hotspots object-store column — i.e. PHP serialized bytes, not JSON.
2. On load, Hotspotimage::getDataFromResource() reads that column, calls json_decode() (which fails for the serialized format), and therefore falls through to Serialize::unserialize($metaData) with the default unrestricted class list.
3. Serialize::unserialize() invokes unserialize($data, ['allowed_classes' => true]), instantiating any class named in the bytes and triggering its magic methods.
4. The load path is exercised on essentially every object retrieval (admin grid/detail, frontend rendering, Studio/API reads, inheritance walks) for objects whose class declares a Hotspotimage field, with a non-null <field>__image.

The attacker primitive is the ability to place crafted serialized bytes into the <field>__hotspots store column (for…