CVE-2025-40301
Description
A flaw was found in the Linux kernel's Bluetooth component. A local attacker with low privileges could exploit a vulnerability in the Host Controller Interface (HCI) event processing. This issue arises from improper handling of command complete events with unknown opcodes, which can lead to the system attempting to read from uninitialized memory. Successful exploitation could result in the disclosure of sensitive information or cause the system to become unavailable (a denial of service).
Mitigation
To mitigate this issue, disable the Bluetooth kernel module if Bluetooth functionality is not required. This can be achieved by blacklisting the `bluetooth` module. Create a file named `/etc/modprobe.d/disable-bluetooth.conf` with the following content: `blacklist bluetooth`. A system reboot is required for this change to take effect. Disabling Bluetooth may impact functionality that relies on Bluetooth connectivity.
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 | 7.1 | N/A | 7.6 |
| Attack Vector | Local | N/A | Adjacent Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | Low |
| Integrity Impact | None | N/A | Low |
| 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:N/A:H
cve.org: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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