CVE-2026-42493
x86 shadow paging is deprecated
Description
Addressing certain issues, in particular related to operations which may take excessively long and therefore would need preemption, has turned out overly costly. Since alternatives (HVM/PVH: HAP, PV: shim) are commonly available, the decision was to deprecate the functionality, while still retaining it for people to use at their own (security) risk. Memory-wise small enough guests may still be okay to run.
INFO
Published Date :
July 28, 2026, 1:18 p.m.
Last Modified :
July 28, 2026, 2:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-42493
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Deprecate the functionality causing excessive operational costs.
- Consider using alternative HVM/PVH or PV implementations.
- Retain functionality at own security risk if needed.
- Evaluate memory usage for small guests.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-42493.
| URL | Resource |
|---|---|
| https://xenbits.xenproject.org/xsa/advisory-495.html | |
| http://xenbits.xen.org/xsa/advisory-495.html |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-42493 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-42493
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-42493 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-42493 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Jul. 28, 2026
Action Type Old Value New Value Added Reference http://xenbits.xen.org/xsa/advisory-495.html -
New CVE Received by [email protected]
Jul. 28, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Xen', 'product': 'Xen', 'versions': [{'status': 'unknown', 'version': 'consult Xen advisory XSA-495'}], 'defaultStatus': 'unknown'}] Added Description Addressing certain issues, in particular related to operations which may take excessively long and therefore would need preemption, has turned out overly costly. Since alternatives (HVM/PVH: HAP, PV: shim) are commonly available, the decision was to deprecate the functionality, while still retaining it for people to use at their own (security) risk. Memory-wise small enough guests may still be okay to run. Added Reference https://xenbits.xenproject.org/xsa/advisory-495.html