DEBIAN-CVE-2021-46904

Advisory lineage Upstream: 1 Downstream: 0
Upstream
Published: 26 Feb 2024, 16:27
Last modified:28 Apr 2026, 20:23

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

26 Feb 2024, 16:27
Published
Vulnerability first disclosed
28 Apr 2026, 20:23
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: net: hso: fix null-ptr-deref during tty device unregistration Multiple ttys try to claim the same the minor number causing a double unregistration of the same device. The first unregistration succeeds but the next one results in a null-ptr-deref. The get_free_serial_index() function returns an available minor number but doesn't assign it immediately. The assignment is done by the caller later. But before this assignment, calls to get_free_serial_index() would return the same minor number. Fix this by modifying get_free_serial_index to assign the minor number immediately after one is found to be and rename it to obtain_minor() to better reflect what it does. Similary, rename set_serial_by_index() to release_minor() and modify it to free up the minor number of the given hso_serial. Every obtain_minor() should have corresponding release_minor() call.

CVSS Metrics

  • v3.1MEDIUMScore: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Systems

  • debianlinux

    < 5.10.38-1 | < 5.10.38-1 | < 5.10.38-1 | < 5.10.38-1

References (1)