CVE-2021-42521

There is a NULL pointer dereference vulnerability in VTK before 9.2.5, and it lies in IO/Infovis/vtkXMLTreeReader.cxx. The vendor didnt check the return value of libxml2 API xmlDocGetRootElement, and try to dereference it. It is unsafe as the return value can be NULL and that NULL pointer dereference may crash the application.

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

Name	Vendor	Start Version	End Version
Vtk	Vtk	*	9.0.0 (including)
Vtk	Ubuntu	trusty	*
Vtk	Ubuntu	trusty/esm	*
Vtk	Ubuntu	xenial	*
Vtk6	Ubuntu	bionic	*
Vtk6	Ubuntu	focal	*
Vtk6	Ubuntu	trusty	*
Vtk6	Ubuntu	trusty/esm	*
Vtk6	Ubuntu	xenial	*
Vtk7	Ubuntu	bionic	*
Vtk7	Ubuntu	focal	*
Vtk7	Ubuntu	kinetic	*
Vtk9	Ubuntu	kinetic	*
Vtk9	Ubuntu	lunar	*
Vtk9	Ubuntu	mantic	*
Vtk9	Ubuntu	oracular	*
Vtk9	Ubuntu	plucky	*

Potential Mitigations

Mitigation of resource exhaustion attacks requires that the target system either:
The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

NVD	https://nvd.nist.gov/vuln/detail/CVE-2021-42521
CWE	https://cwe.mitre.org/data/definitions/400.html

Uncontrolled Resource Consumption

Weakness

Affected Software

Potential Mitigations

References

CVE-2021-42521

Uncontrolled Resource Consumption

Weakness

Affected Software

Potential Mitigations

Related Attack Patterns

References