CVE-2026-98285
Description
A flaw was found in the Linux kernel's network bridge component. When removing Virtual Local Area Network (VLAN) configurations, errors returned by hardware offload devices prevent the kernel from completing software cleanup. A local user could exploit this vulnerability to trigger memory leaks or a null pointer dereference, leading to a system crash and a Denial of Service (DoS).
Statement
A flaw of low impact was found in the Linux kernel's network bridge VLAN subsystem, affecting the Red Hat Enterprise Linux kernel and kernel-rt packages, the Red Hat In-Vehicle OS kernels, and the Red Hat CoreOS kernel builds shipped with OpenShift Container Platform. When a bridge VLAN is deleted, an error returned by a switchdev hardware offload device could abort the kernel's software VLAN cleanup in __vlan_del. This could leave the bridge VLAN state inconsistent, leak memory when VLANs are flushed, or cause a NULL pointer dereference on the bridge error path when flushing. A local user able to configure bridge VLANs (which requires CAP_NET_ADMIN) on a host whose bridge ports are offloaded to switchdev-capable hardware could use this to crash the kernel, resulting in a local denial of service. Red Hat Enterprise Linux 6 is not affected because the vulnerable code is not present in that release. Red Hat Product Security rates this issue Low impact because exploitation requires local privileged access and depends on a switchdev deletion error occurring, and the impact is limited to system availability. Because of this low impact, the fix is deferred to a future update of the affected products; the residual risk is a local, privilege-gated denial of service with no impact on confidentiality or integrity.
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: Crash, Exit, or Restart
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
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