The application does not validate the presence of required appearance (AP) data before accessing stamp annotation resources. When a PDF contains a stamp annotation missing its AP entry, the code continues to dereference the associated object without a prior null or validity check, which allows a crafted document to trigger a null pointer dereference and crash the application, resulting in denial of service.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
Required
User action required
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1