CVE-2026-99232
Description
A flaw was found in the Linux kernel. A local attacker can trigger this issue by invoking faultable system calls with non-user memory addresses while tracing is active. Because the kernel fails to verify that the source address resides in user space before copying data into trace buffers, this flaw may lead to information disclosure of sensitive kernel memory.
Statement
This vulnerability is rated as Moderate severity because exploitation is confined to local environments and depends on active syscall tracing, which is disabled by default on standard Red Hat Enterprise Linux installations. An unprivileged local user cannot trigger trace event capture unless an administrator or privileged monitoring process explicitly enables tracing of faultable system calls. While unauthorized disclosure of kernel memory could expose sensitive system details, the defect does not allow arbitrary privilege escalation or system disruption directly.
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 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | High | 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 | High | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | None | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
If the dereferencing operation is for a read, then the attack might allow reading of sensitive data, cause a crash, or set a variable to an unexpected value (since the value will be read from an unexpected memory location).
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If the untrusted pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" or larger than expected by a read or write operation, the application may terminate unexpectedly.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands; Modify Memory
If the pointer is dereferenced for a write operation, the attack might allow modification of critical state variables, cause a crash, or execute code. If the untrusted pointer is used in a function call, then the attacker might be able to call arbitrary functions.
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