Main Vulnerability Database Vulnerabilities #VU138828

Improper handling of exceptional conditions in Linux kernel - CVE-2026-63821

Published: July 21, 2026

Vulnerability identifier: #VU138828

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-63821

CWE-ID: CWE-755

Exploitation vector: Local access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper exception handling in rtw_usb_write_data() and rtw_usb_tx_agg_skb() when handling USB write submission failures. A local user can trigger a USB write failure to cause a denial of service.

The issue can be triggered during device disconnect or reconnect scenarios and under memory pressure conditions.

Affected software

Linux kernel

How to mitigate CVE-2026-63821

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3

External References

Related Security Bulletins