CVE-2026-118445: Use-after-free in INSTRUX structure members in pybddisasm
A use-after-free vulnerability in the pybddisasm Python bindings affects structure-valued members of INSTRUX objects. These members are exposed through Python objects that reference memory owned by the parent INSTRUX object. A retained reference to a member does not keep the parent allocation alive. Accessing the member after the parent INSTRUX object has been freed therefore accesses freed memory. Depending on how the member is used and whether the freed allocation has been reused, this may expose process memory or cause the Python process to crash. Exploitation requires an application to retain and subsequently access a member reference after the parent object has been freed. The pybddisasm package is no longer maintained.
Event History
Frequently Asked Questions
What application behavior is required for exploitation?
The application must retain a reference to a structure-valued member of an INSTRUX object, allow the parent INSTRUX object to be freed, and then access the retained member reference. A local attacker with low privileges is indicated by the supplied vector.
What is the likely impact if the vulnerable reference is accessed?
Access may read freed memory and expose process memory, or it may cause the Python process to crash. The actual result depends on how the member is used and whether the freed allocation has been reused.
Is an upstream fix available?
No fixed version or patch is provided in the available data. The pybddisasm package is no longer maintained.