CVE-2021-46905: net: hso: fix NULL-deref on disconnect regression
In the Linux kernel, the following vulnerability has been resolved:
net: hso: fix NULL-deref on disconnect regression
Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") fixed the racy minor allocation reported by syzbot, but introduced an unconditional NULL-pointer dereference on every disconnect instead.
Specifically, the serial device table must no longer be accessed after the minor has been released by hsoserialttyunregister().
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2021-46905?
The severity of CVE-2021-46905 is classified as medium due to the potential for denial-of-service conditions.
How do I fix CVE-2021-46905?
To fix CVE-2021-46905, update the Linux kernel to version 5.12 or later, or apply the appropriate patches.
What causes CVE-2021-46905?
CVE-2021-46905 is caused by a null pointer dereference in the HSO driver during device disconnection.
Which versions of the Linux kernel are affected by CVE-2021-46905?
CVE-2021-46905 affects Linux kernel versions from 4.20.0 up to but not including 5.12.
Is CVE-2021-46905 a remote exploit?
CVE-2021-46905 is not a remote exploit; it requires local access to trigger the vulnerability.