CVE-2024-45818
Xen Hypervisor Deadlock Vulnerability
Description
The hypervisor contains code to accelerate VGA memory accesses for HVM guests, when the (virtual) VGA is in "standard" mode. Locking involved there has an unusual discipline, leaving a lock acquired past the return from the function that acquired it. This behavior results in a problem when emulating an instruction with two memory accesses, both of which touch VGA memory (plus some further constraints which aren't relevant here). When emulating the 2nd access, the lock that is already being held would be attempted to be re-acquired, resulting in a deadlock. This deadlock was already found when the code was first introduced, but was analysed incorrectly and the fix was incomplete. Analysis in light of the new finding cannot find a way to make the existing locking discipline work. In staging, this logic has all been removed because it was discovered to be accidentally disabled since Xen 4.7. Therefore, we are fixing the locking problem by backporting the removal of most of the feature. Note that even with the feature disabled, the lock would still be acquired for any accesses to the VGA MMIO region.
INFO
Published Date :
Dec. 19, 2024, 12:15 p.m.
Last Modified :
May 20, 2025, 4:28 p.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
4.0
Exploitability Score :
2.0
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-2024-45818.
| URL | Resource |
|---|---|
| https://xenbits.xenproject.org/xsa/advisory-463.html | Patch Vendor Advisory |
| http://www.openwall.com/lists/oss-security/2024/11/12/2 | Patch Third Party Advisory |
| http://xenbits.xen.org/xsa/advisory-463.html | Patch Vendor Advisory |
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-2024-45818 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2024-45818 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.
-
Initial Analysis by [email protected]
May. 20, 2025
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:o:xen:xen:*:*:*:*:*:*:x86:* versions from (including) 4.6.0 up to (excluding) 4.20.0 Added Reference Type CVE: http://www.openwall.com/lists/oss-security/2024/11/12/2 Types: Patch, Third Party Advisory Added Reference Type CVE: http://xenbits.xen.org/xsa/advisory-463.html Types: Patch, Vendor Advisory Added Reference Type Xen Project: https://xenbits.xenproject.org/xsa/advisory-463.html Types: Patch, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Dec. 31, 2024
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N Added CWE CWE-667 -
New CVE Received by [email protected]
Dec. 19, 2024
Action Type Old Value New Value Added Description The hypervisor contains code to accelerate VGA memory accesses for HVM guests, when the (virtual) VGA is in "standard" mode. Locking involved there has an unusual discipline, leaving a lock acquired past the return from the function that acquired it. This behavior results in a problem when emulating an instruction with two memory accesses, both of which touch VGA memory (plus some further constraints which aren't relevant here). When emulating the 2nd access, the lock that is already being held would be attempted to be re-acquired, resulting in a deadlock. This deadlock was already found when the code was first introduced, but was analysed incorrectly and the fix was incomplete. Analysis in light of the new finding cannot find a way to make the existing locking discipline work. In staging, this logic has all been removed because it was discovered to be accidentally disabled since Xen 4.7. Therefore, we are fixing the locking problem by backporting the removal of most of the feature. Note that even with the feature disabled, the lock would still be acquired for any accesses to the VGA MMIO region. Added Reference https://xenbits.xenproject.org/xsa/advisory-463.html -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Dec. 19, 2024
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2024/11/12/2 Added Reference http://xenbits.xen.org/xsa/advisory-463.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-2024-45818 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-2024-45818
weaknesses.