CVE-2026-97477
Description
A flaw was found in the Linux kernel's Remote Direct Memory Access (RDMA) subsystem. An error-handling issue during counter allocation and queue pair binding neglects to decrement the active counter tally when a bind attempt fails. A local user can exploit this flaw by triggering repeated binding failures, which leaks counter references and permanently prevents the port from switching operational modes, resulting in a denial of service.
Statement
A low impact denial of service flaw was found in the Linux kernel's RDMA (Remote Direct Memory Access) subsystem. When binding a queue pair to a counter fails in alloc_and_bind(), the error path frees the counter without decrementing port_counter->num_counters. A local user with access to RDMA resources can trigger repeated binding failures to leak counter references, which permanently prevents the affected RDMA port from switching counter modes: switching to AUTO mode fails with -EBUSY and the automatic MANUAL-to-NONE revert is blocked. The result is a local denial of service limited to RDMA counter mode management on the affected port; confidentiality and integrity are not affected. Red Hat Product Security has rated this flaw as Low impact, which is lower than the moderate severity implied by the Red Hat CVSS 3.1 base score of 5.5 (AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H), because exploitation requires local access to RDMA-capable hardware and the consequence is confined to degraded counter mode management. Affected Red Hat products include the kernel, kernel-rt, and kernel-ivos-qualcomm components as well as OpenShift RHEL CoreOS 8 and 9; certain versions are not affected because the vulnerable code is not present. Because of the low assessed impact, fixes are currently deferred for the affected products; the residual risk is a local denial of service limited to RDMA counter mode switching on affected ports.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
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 | 5.5 | 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 | High | 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:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
An adversary that can cause a resource counter to become inaccurate may be able to create situations where resources are not accounted for and not released, thus causing resources to become scarce for future needs.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An adversary that can cause a resource counter to become inaccurate may be able to force an error that causes the product to crash or exit out of its current operation.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
