CVE-2025-38303
kernel: Bluetooth: eir: Fix possible crashes on eir_create_adv_data
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 10, 2025
Updated · July 30, 2026
Description
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: eir: Fix possible crashes on eir_create_adv_data
eir_create_adv_data may attempt to add EIR_FLAGS and EIR_TX_POWER without checking if that would fit.
Statement
A vulnerability in eir_create_adv_data() in the Linux Bluetooth stack (introduced in commit 01ce70b0a274) may lead to out-of-bounds memory writes due to the lack of bounds checking when adding EIR fields like EIR_FLAGS and EIR_TX_POWER. This can cause kernel crashes when oversized advertising data is constructed. The bug is fixed by adding explicit size checks before writing into the advertising data buffer. Exploitation leads to a kernel crash (Oops) or memory corruption when the Bluetooth advertising data overflows the target buffer. It does not affect confidentiality or integrity, but can impact availability. Only privileged processes with direct access to Bluetooth HCI configuration interfaces (e.g., kernel threads or root-initiated bluetoothd context) can trigger this code path. Regular unprivileged users cannot invoke it without elevated rights. Although the vulnerability involves memory corruption in kernel space, it occurs in a Bluetooth advertising data generation function that is not directly accessible to unprivileged users. Triggering the flaw requires high privileges (PR:H), and there is no evidence that the corruption can be exploited to gain code execution or affect confidentiality or integrity. The primary impact is a kernel crash, which justifies marking only Availability as High while leaving Confidentiality and Integrity as None.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 4.4CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer