CVE-2026-23345
Description
A flaw was found in the Linux kernel. When the FEAT_LPA2 feature is enabled on ARM64 systems, the kernel incorrectly handles the PTE_SHARED bits in Graphics Control System (GCS) memory mappings. This misconfiguration can lead to a kernel paging request and subsequently a system panic, resulting in a Denial of Service (DoS). A local user or specific system configuration could trigger this vulnerability.
Statement
This flaw is specific to ARM64 systems with both FEAT_LPA2 (Large Physical Address 2) and GCS (Guarded Control Stack) enabled. When LPA2 is active, PTE bits 8-9 have a different meaning than shareability, causing incorrect address translation for GCS mappings. This is an uncommon hardware configuration combination, primarily affecting newer ARM platforms.
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 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | 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:L/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)
Access Control
Technical Impact: Gain Privileges or Assume Identity
The attacker can gain access to otherwise unauthorized resources.
Integrity,Confidentiality,Other
Technical Impact: Modify Application Data; Modify Files or Directories; Read Application Data; Read Files or Directories; Other
Race conditions such as this kind may be employed to gain read or write access to resources not normally readable or writable by the user in question.
Integrity,Other
Technical Impact: Modify Application Data; Other
The resource in question, or other resources (through the corrupted one) may be changed in undesirable ways by a malicious user.
Non-Repudiation
Technical Impact: Hide Activities
If a file or other resource is written in this method, as opposed to a valid way, logging of the activity may not occur.
Non-Repudiation,Integrity
Technical Impact: Modify Files or Directories
In some cases it may be possible to delete files that a malicious user might not otherwise have access to -- such as log files.
Frequently Asked Questions
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