Xpdf 4.04 will deadlock on a PDF object stream whose Length field is itself in another object stream.
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Xpdf | Xpdfreader | 4.04 (including) | 4.04 (including) |
| Ipe | Ubuntu | bionic | * |
| Ipe | Ubuntu | kinetic | * |
| Ipe | Ubuntu | lunar | * |
| Ipe | Ubuntu | mantic | * |
| Ipe | Ubuntu | trusty | * |
| Ipe | Ubuntu | xenial | * |
| Xpdf | Ubuntu | bionic | * |
| Xpdf | Ubuntu | kinetic | * |
| Xpdf | Ubuntu | lunar | * |
| Xpdf | Ubuntu | mantic | * |
| Xpdf | Ubuntu | trusty | * |
| Xpdf | Ubuntu | xenial | * |
Locking is a type of synchronization behavior that ensures that multiple independently-operating processes or threads do not interfere with each other when accessing the same resource. All processes/threads are expected to follow the same steps for locking. If these steps are not followed precisely - or if no locking is done at all - then another process/thread could modify the shared resource in a way that is not visible or predictable to the original process. This can lead to data or memory corruption, denial of service, etc.