CVE-2021-43389
kernel: an array-index-out-bounds in detach_capi_ctr in drivers/isdn/capi/kcapi.c
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 24, 2021
Updated · June 28, 2026
Description
An improper validation of an array index and out of bounds memory read in the Linux kernel's Integrated Services Digital Network (ISDN) functionality was found in the way users call ioctl CMTPCONNADD. A local user could use this flaw to crash the system or starve the resources causing denial of service.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
To mitigate this issue, prevent the module isdn from being loaded. Please see https://access.redhat.com/solutions/41278 for information on how to blacklist a kernel module to prevent it from loading automatically.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-125 · Out-of-bounds Read