CVE-2025-21695
Dell UART Backlight Null Pointer Dereference
Description
In the Linux kernel, the following vulnerability has been resolved: platform/x86: dell-uart-backlight: fix serdev race The dell_uart_bl_serdev_probe() function calls devm_serdev_device_open() before setting the client ops via serdev_device_set_client_ops(). This ordering can trigger a NULL pointer dereference in the serdev controller's receive_buf handler, as it assumes serdev->ops is valid when SERPORT_ACTIVE is set. This is similar to the issue fixed in commit 5e700b384ec1 ("platform/chrome: cros_ec_uart: properly fix race condition") where devm_serdev_device_open() was called before fully initializing the device. Fix the race by ensuring client ops are set before enabling the port via devm_serdev_device_open(). Note, serdev_device_set_baudrate() and serdev_device_set_flow_control() calls should be after the devm_serdev_device_open() call.
INFO
Published Date :
Feb. 12, 2025, 2:15 p.m.
Last Modified :
Feb. 14, 2025, 3:44 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the Linux kernel to the latest version.
- Apply the provided patch for the dell-uart-backlight driver.
- Ensure serdev client ops are set before opening the device.
- Test the updated driver for stability and correct operation.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-21695.
| URL | Resource |
|---|---|
| https://git.kernel.org/stable/c/1b2128aa2d45ab20b22548dcf4b48906298ca7fd | Patch |
| https://git.kernel.org/stable/c/d3a24d923333f75aaece9acb051d676edc0afb75 | Patch |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-21695 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-21695
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-21695 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-21695 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Feb. 14, 2025
Action Type Old Value New Value Added CVSS V3.1 NIST AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE NIST CWE-476 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.10 up to (excluding) 6.12.11 *cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:* Changed Reference Type https://git.kernel.org/stable/c/1b2128aa2d45ab20b22548dcf4b48906298ca7fd No Types Assigned https://git.kernel.org/stable/c/1b2128aa2d45ab20b22548dcf4b48906298ca7fd Patch Changed Reference Type https://git.kernel.org/stable/c/d3a24d923333f75aaece9acb051d676edc0afb75 No Types Assigned https://git.kernel.org/stable/c/d3a24d923333f75aaece9acb051d676edc0afb75 Patch -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Feb. 12, 2025
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: platform/x86: dell-uart-backlight: fix serdev race The dell_uart_bl_serdev_probe() function calls devm_serdev_device_open() before setting the client ops via serdev_device_set_client_ops(). This ordering can trigger a NULL pointer dereference in the serdev controller's receive_buf handler, as it assumes serdev->ops is valid when SERPORT_ACTIVE is set. This is similar to the issue fixed in commit 5e700b384ec1 ("platform/chrome: cros_ec_uart: properly fix race condition") where devm_serdev_device_open() was called before fully initializing the device. Fix the race by ensuring client ops are set before enabling the port via devm_serdev_device_open(). Note, serdev_device_set_baudrate() and serdev_device_set_flow_control() calls should be after the devm_serdev_device_open() call. Added Reference https://git.kernel.org/stable/c/1b2128aa2d45ab20b22548dcf4b48906298ca7fd Added Reference https://git.kernel.org/stable/c/d3a24d923333f75aaece9acb051d676edc0afb75