In the Linux kernel, the following vulnerability has been resolved:

USB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb()

This patch addresses a null-ptr-deref in qt2_process_read_urb() due to
an incorrect bounds check in the following:

if (newport > serial->num_ports) {
dev_err(&port->dev,
"%s - port change to invalid port: %i\n",
__func__, newport);
break;
}

The condition doesn't account for the valid range of the serial->port
buffer, which is from 0 to serial->num_ports - 1. When newport is equal
to serial->num_ports, the assignment of "port" in the
following code is out-of-bounds and NULL:

serial_priv->current_port = newport;
port = serial->port[serial_priv->current_port];

The fix checks if newport is greater than or equal to serial->num_ports
indicating it is out-of-bounds.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-4075-1 linux security update
Debian DLA Debian DLA DLA-4076-1 linux-6.1 security update
EUVD EUVD EUVD-2025-2638 In the Linux kernel, the following vulnerability has been resolved: USB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb() This patch addresses a null-ptr-deref in qt2_process_read_urb() due to an incorrect bounds check in the following: if (newport > serial->num_ports) { dev_err(&port->dev, "%s - port change to invalid port: %i\n", __func__, newport); break; } The condition doesn't account for the valid range of the serial->port buffer, which is from 0 to serial->num_ports - 1. When newport is equal to serial->num_ports, the assignment of "port" in the following code is out-of-bounds and NULL: serial_priv->current_port = newport; port = serial->port[serial_priv->current_port]; The fix checks if newport is greater than or equal to serial->num_ports indicating it is out-of-bounds.
Ubuntu USN Ubuntu USN USN-7387-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7387-2 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7387-3 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7388-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7389-1 Linux kernel (NVIDIA Tegra) vulnerabilities
Ubuntu USN Ubuntu USN USN-7390-1 Linux kernel (Xilinx ZynqMP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7391-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-3 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7392-4 Linux kernel (AWS FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7393-1 Linux kernel (FIPS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7401-1 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-7407-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-7413-1 Linux kernel (IoT) vulnerabilities
Ubuntu USN Ubuntu USN USN-7421-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7445-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7448-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7458-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7459-1 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-7459-2 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-7463-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-7539-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7540-1 Linux kernel (Raspberry Pi) vulnerabilities
Ubuntu USN Ubuntu USN USN-7595-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7595-2 Linux kernel (Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7595-3 Linux kernel (Raspberry Pi Real-time) vulnerabilities
Ubuntu USN Ubuntu USN USN-7595-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7595-5 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7596-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7596-2 Linux kernel (Azure, N-Series) vulnerabilities
Ubuntu USN Ubuntu USN USN-7653-1 Linux kernel (HWE) vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 03 Nov 2025 21:30:00 +0000


Wed, 01 Oct 2025 20:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00017}

epss

{'score': 0.00018}


Wed, 14 May 2025 03:00:00 +0000

Type Values Removed Values Added
First Time appeared Redhat
Redhat enterprise Linux
CPEs cpe:/a:redhat:enterprise_linux:9
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux

Fri, 21 Feb 2025 17:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.13:-:*:*:*:*:*:*
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:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel

Wed, 19 Feb 2025 15:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-476

Fri, 14 Feb 2025 03:00:00 +0000

Type Values Removed Values Added
Metrics threat_severity

Important

threat_severity

Moderate


Tue, 11 Feb 2025 13:45:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Important


Mon, 10 Feb 2025 16:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: USB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb() This patch addresses a null-ptr-deref in qt2_process_read_urb() due to an incorrect bounds check in the following: if (newport > serial->num_ports) { dev_err(&port->dev, "%s - port change to invalid port: %i\n", __func__, newport); break; } The condition doesn't account for the valid range of the serial->port buffer, which is from 0 to serial->num_ports - 1. When newport is equal to serial->num_ports, the assignment of "port" in the following code is out-of-bounds and NULL: serial_priv->current_port = newport; port = serial->port[serial_priv->current_port]; The fix checks if newport is greater than or equal to serial->num_ports indicating it is out-of-bounds.
Title USB: serial: quatech2: fix null-ptr-deref in qt2_process_read_urb()
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-11-03T20:59:10.756Z

Reserved: 2024-12-29T08:45:45.741Z

Link: CVE-2025-21689

cve-icon Vulnrichment

Updated: 2025-10-01T15:59:46.997Z

cve-icon NVD

Status : Modified

Published: 2025-02-10T16:15:38.447

Modified: 2025-11-03T21:19:08.123

Link: CVE-2025-21689

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-02-10T00:00:00Z

Links: CVE-2025-21689 - Bugzilla

cve-icon OpenCVE Enrichment

No data.