VDB-315789 · CVE-2025-38262 · EUVD-2025-20799

Linux Kernel up to 6.1.142/6.6.95/6.12.35/6.15.4 tty uart_register_driver null pointer dereference

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0	$0-$5k	0.75

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.142/6.6.95/6.12.35/6.15.4. It has been classified as critical. Affected by this issue is the function uart_register_driver of the component tty. Performing a manipulation results in null pointer dereference. This vulnerability is cataloged as CVE-2025-38262. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.142/6.6.95/6.12.35/6.15.4. It has been classified as critical. This affects the function uart_register_driver of the component tty. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: tty: serial: uartlite: register uart driver in init When two instances of uart devices are probing, a concurrency race can occur. If one thread calls uart_register_driver function, which first allocates and assigns memory to 'uart_state' member of uart_driver structure, the other instance can bypass uart driver registration and call ulite_assign. This calls uart_add_one_port, which expects the uart driver to be fully initialized. This leads to a kernel panic due to a null pointer dereference: [ 8.143581] BUG: kernel NULL pointer dereference, address: 00000000000002b8 [ 8.156982] #PF: supervisor write access in kernel mode [ 8.156984] #PF: error_code(0x0002) - not-present page [ 8.156986] PGD 0 P4D 0 ... [ 8.180668] RIP: 0010:mutex_lock+0x19/0x30 [ 8.188624] Call Trace: [ 8.188629] ? __die_body.cold+0x1a/0x1f [ 8.195260] ? page_fault_oops+0x15c/0x290 [ 8.209183] ? __irq_resolve_mapping+0x47/0x80 [ 8.209187] ? exc_page_fault+0x64/0x140 [ 8.209190] ? asm_exc_page_fault+0x22/0x30 [ 8.209196] ? mutex_lock+0x19/0x30 [ 8.223116] uart_add_one_port+0x60/0x440 [ 8.223122] ? proc_tty_register_driver+0x43/0x50 [ 8.223126] ? tty_register_driver+0x1ca/0x1e0 [ 8.246250] ulite_probe+0x357/0x4b0 [uartlite] To prevent it, move uart driver registration in to init function. This will ensure that uart_driver is always registered when probe function is called.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-38262 since 04/16/2025. The exploitability is told to be difficult. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 265984 (Ubuntu Pro FIPS-updates 22.04 LTS : Linux kernel (Azure FIPS) vulnerabilities (USN-7775-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.143, 6.6.96, 6.12.36, 6.15.5 or 6.16-rc1 eliminates this vulnerability. Applying the patch 6db06aaea07bb7c8e33a425cf7b98bf29ee6056e/8e958d10dd0ce5ae674cce460db5c9ca3f25243b/685d29f2c5057b32c7b1b46f2a7d303b926c8f72/f5e4229d94792b40e750f30c92bcf7a3107c72ef/6bd697b5fc39fd24e2aa418c7b7d14469f550a93 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (265984), EUVD (EUVD-2025-20799) and CERT Bund (WID-SEC-2025-1517). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

Debian Linux
Google Cloud Platform
Red Hat Enterprise Linux
Ubuntu Linux
SUSE Linux
Oracle Linux
IBM QRadar SIEM
SUSE openSUSE
NetApp ActiveIQ Unified Manager
Dell Avamar
Open Source Linux Kernel
Dell NetWorker
Dell Secure Connect Gateway

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.0
VulDB Meta Temp Score: 6.0

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector (Linux): 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍