Kernel crash via USB serial hangup race
Published Oct 18, 2026 · Updated Oct 18, 2026
A race in Linux USB serial ioctl handling allows local users to trigger a kernel NULL-pointer crash when a device disconnects. In drivers/usb/serial/usb-serial.c, callbacks including serial_break access driver state without serialization against hangup or a check that the port remains usable. Exploitation requires access to the affected tty and a concurrent hangup, such as disconnection during prolonged break signaling; no code execution is established.
Summary
What happened
A race in Linux USB serial ioctl handling allows local users to trigger a kernel NULL-pointer crash when a device disconnects. In drivers/usb/serial/usb-serial.c, callbacks including serial_break access driver state without serialization against hangup or a check that the port remains usable. Exploitation requires access to the affected tty and a concurrent hangup, such as disconnection during prolonged break signaling; no code execution is established.
The record
- CVE
- CVE-2026-98695
- Published
- Oct 18, 2026
- Updated
- Oct 18, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499.004
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Oct 18, 2026CVE publishedPublication date reported by the CVE source.
- Oct 18, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.6.26
- Affected versionversion=f34d7a5b7010b82fe97da95496b9971435530062 <4597ddd6168ae2a4123404e5f0871f1070dc7773
- Affected versionversion=f34d7a5b7010b82fe97da95496b9971435530062 <7912a95d1345c77d8d63b530b00c118700b78abd
- Affected versionversion=f34d7a5b7010b82fe97da95496b9971435530062 <ae0da9a5c1ca95c20cc5feffd511ce6eae75924e
- Affected versionversion=f34d7a5b7010b82fe97da95496b9971435530062 <ae0e61d95677efa778379853e495d748e6efbf95
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Get started