CVE-2026-31781
Description
A flaw was found in the Linux kernel's Direct Rendering Manager (DRM) subsystem, specifically in the drm/ioc32 component. This vulnerability, related to speculative execution (a technique used by modern processors to guess future instructions), allows a local attacker to potentially disclose sensitive information. The drm_compat_ioctl path incorrectly handles user-controlled pointers, leading to a Spectre-like issue where data can be exposed through speculative execution side channels.
Statement
32-bit DRM compat ioctl must not speculate past validated user indices. Red Hat treats this as Spectre-class hardening for /dev/dri compat paths. Install updated kernels with the DRM fix.
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 | 4.7 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | High | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Covert storage channels may provide attackers with important information about the system in question.
Integrity,Confidentiality
Technical Impact: Read Application Data
If these messages or packets are sent with unnecessary data contained within, it may tip off malicious listeners as to the process that created the message. With this information, attackers may learn any number of things, including the hardware platform, operating system, or algorithms used by the sender. This information can be of significant value to the user in launching further attacks.
Frequently Asked Questions
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