CVE-2021-47575
Description
[REJECTED CVE] The Xen console driver (hvc_xen) has a bug in event channel storms, where an excessive number of events sent by the backend could overwhelm the system. The issue stemmed from sending events even when no bytes were read from the backend, causing unnecessary interrupts. Additionally, during the domU initial console setup, there was no XenBus device available when the event channel was bound, complicating event handling.
Statement
This CVE has been rejected upstream: https://lore.kernel.org/linux-cve-announce/2024062012-REJECTED-9525@gregkh/
Red Hat has also evaluated this issue and determined that it does not meet the criteria to be classified as a security vulnerability. This assessment is based on the issue not posing a significant security risk, being a result of misconfiguration or usage error, or falling outside the scope of security considerations.
As such, this CVE has been marked as "Rejected" in alignment with Red Hat's vulnerability management policies.
If you have additional information or concerns regarding this determination, please contact Red Hat Product Security for further clarification.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 0 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | None | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:N
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
If an attacker can trigger the allocation of the limited resources, but the number or size of the resources is not controlled, then the most common result is denial of service. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment, i.e., the product may slow down, crash due to unhandled errors, or lock out legitimate users. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system.
Access Control,Other
Technical Impact: Bypass Protection Mechanism; Other
In some cases it may be possible to force the product to "fail open" in the event of resource exhaustion. The state of the product -- and possibly the security functionality - may then be compromised.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
