CVE-2022-42319

Xenstore: Guests can cause Xenstore to not free temporary memory When working on a request of a guest, xenstored might need to allocate quite large amounts of memory temporarily. This memory is freed only after the request has been finished completely. A request is regarded to be finished only after the guest has read the response message of the request from the ring page. Thus a guest not reading the response can cause xenstored to not free the temporary memory. This can result in memory shortages causing Denial of Service (DoS) of xenstored.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Name	Vendor	Start Version	End Version
Xen	Xen	4.9.0 (including)	*
Xen	Ubuntu	bionic	*
Xen	Ubuntu	kinetic	*
Xen	Ubuntu	lunar	*
Xen	Ubuntu	mantic	*
Xen	Ubuntu	trusty	*
Xen	Ubuntu	xenial	*

Potential Mitigations

Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
For example, glibc in Linux provides protection against free of invalid pointers.
When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

NVD	https://nvd.nist.gov/vuln/detail/CVE-2022-42319
CWE	https://cwe.mitre.org/data/definitions/401.html

Missing Release of Memory after Effective Lifetime

Weakness

Affected Software

Potential Mitigations

References