CVE-2021-46905

CVE-2021-46905 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Description

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 hso_serial_tty_unregister().

Frequently asked questions

What is CVE-2021-46905?
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 hso_serial_tty_unregister().
How severe is CVE-2021-46905?
CVE-2021-46905 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-46905 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46905?
CVE-2021-46905 primarily affects Linux Linux Kernel. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-46905?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-46905 have an EU (EUVD) identifier?
Yes. CVE-2021-46905 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33553.
When was CVE-2021-46905 published?
CVE-2021-46905 was published on 2024-02-26 and last updated on 2026-06-17.

References

Affected products (9)

More vulnerabilities in Linux Linux Kernel

All CVEs affecting Linux Linux Kernel →

Other CWE-476 (NULL Pointer Dereference) vulnerabilities

Browse all CWE-476 (NULL Pointer Dereference) vulnerabilities →