Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2024-45818— Deadlock in x86 HVM standard VGA handling

Quick assessment

Affected
Xen Xen
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Xen是Xen开源的一款开源的虚拟机监视器产品。该产品能够使不同和不兼容的操作系统运行在同一台计算机上，并支持在运行时进行迁移，保证正常运行并且避免宕机。 Xen存在安全漏洞，该漏洞源于hypervisor中VGA内存访问加速代码的锁定规则设计不当，以及历史问题处理不彻底导致的死锁问题。

AI Predicted 4.4 Difficulty: Hard EPSS 0.27% · P18

Possible ATT&CK Techniques 1 AI

T1203 · Exploitation for Client Execution
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2024-45818

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Deadlock in x86 HVM standard VGA handling
Source: CVE Program / CVE List V5
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.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Xen 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Xen是Xen开源的一款开源的虚拟机监视器产品。该产品能够使不同和不兼容的操作系统运行在同一台计算机上，并支持在运行时进行迁移，保证正常运行并且避免宕机。 Xen存在安全漏洞，该漏洞源于hypervisor中VGA内存访问加速代码的锁定规则设计不当，以及历史问题处理不彻底导致的死锁问题。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Xen Xen consult Xen advisory XSA-463 -

II. Public POCs for CVE-2024-45818

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2024-45818

请登录查看更多情报信息。

Vendor Advisories for CVE-2024-45818 (1)

Same Patch Batch · Xen · 2024-12-19 · 3 CVEs total

CVE-2024-2201 CVE-2024-2201
CVE-2024-45819 libxl leaks data to PVH guests via ACPI tables

IV. Related Vulnerabilities

Same product: Xen
Same vendor: Xen

V. Comments for CVE-2024-45818

No comments yet

Leave a comment