x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 6.4, requiring local system access to exploit but requires specific conditions to be met without requiring user interaction . The vulnerability impacts confidentiality (data exposure), integrity (unauthorized modifications), and availability (service disruption) for affected systems. Impacting 3 products from xen, from fedoraproject, from debian organizations running these solutions should prioritize assessment and patching.
Reported in 2022, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2022-06-09T17:15:08.957
2024-11-21T06:53:49.957
Modified
CVSSv3.1: 6.4 (MEDIUM)
AV:L/AC:M/Au:N/C:C/I:C/A:C
3.4
10.0
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | xen | xen | * | Yes |
| Operating System | fedoraproject | fedora | 35 | Yes |
| Operating System | fedoraproject | fedora | 36 | Yes |
| Operating System | debian | debian_linux | 11.0 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For xen's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.