CVE-2026-93262
Description
A flaw was found in the Linux kernel. A local attacker can cause a Denial of Service (DoS) or potentially escalate privileges through a use-after-free vulnerability in the RAID-5 Partial Parity Log (PPL) component. During flush operations, the system improperly continues to access an input/output (I/O) tracking structure after it has already been released. This memory corruption can destabilize the operating system and cause the kernel to crash.
Mitigation
Prevent the `raid456` kernel module from loading if software RAID 4, 5, or 6 functionality is not required.
1. Add the blacklist configuration by creating `/etc/modprobe.d/blacklist-raid456.conf` with the following entries:
blacklist raid456
install raid456 /bin/true
2. Unload the module if it is currently loaded:
# modprobe -r raid456
Warning: If software RAID 4, 5, or 6 is currently in use or required for storage arrays, this workaround cannot be applied, as disabling the module will prevent storage devices from functioning. A system reboot may be required if the module is actively in use by existing mounts.
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).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.3 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | Low | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
If the expired pointer is used in a read operation, an attacker might be able to control data read in by the application.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If the expired pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If the expired pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.
Frequently Asked Questions
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