An exploitable heap-based buffer overflow vulnerability exists in the PlanMaker document parsing functionality of SoftMaker Office 2021’s PlanMaker application. A specially crafted document can cause the document parser to explicitly trust a length from a particular record type and use it to write a 16-bit null relative to a buffer allocated on the stack. Due to a lack of bounds-checking on this value, this can allow an attacker to write to memory outside of the buffer and controllably corrupt memory. This can allow an attacker to earn code execution under the context of the application. An attacker can entice the victim to open a document to trigger this vulnerability.

A specially crafted document can cause the document parser to copy data from a particular record type into a static-sized buffer within an object that is smaller than the size used for the copy, which will cause a heap-based buffer overflow. In version/Instance 0x0003 and 0x0014, an attacker can entice the victim to open a document to trigger this vulnerability. This affects SoftMaker Software GmbH SoftMaker Office PlanMaker 2021 (Revision 1014).

An exploitable signed conversion vulnerability exists in the TextMaker document parsing functionality of SoftMaker Office 2021’s TextMaker application. A specially crafted document can cause the document parser to miscalculate a length used to allocate a buffer, later upon usage of this buffer the application will write outside its bounds resulting in a heap-based memory corruption. An attacker can entice the victim to open a document to trigger this vulnerability.

An exploitable sign extension vulnerability exists in the TextMaker document parsing functionality of SoftMaker Office 2021’s TextMaker application. A specially crafted document can cause the document parser to sign-extend a length used to terminate a loop, which can later result in the loop’s index being used to write outside the bounds of a heap buffer during the reading of file data. An attacker can entice the victim to open a document to trigger this vulnerability.