CVE-2021-43389 Other in n/a

What is CVE-2021-43389?

CVE-2021-43389 is a medium-severity vulnerability in Debian Debian Linux, published on 4 Nov 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An issue was discovered in the Linux kernel before 5.14.15. There is an array-index-out-of-bounds flaw in the detach_capi_ctr function in drivers/isdn/capi/kcapi.c.

Weakness: CWE-125

Which versions are affected by CVE-2021-43389?

It affects 6 products.

Products include Debian Debian Linux, Linux kernel, Oracle Communications Cloud Native Core Binding Support Function, Oracle Communications Cloud Native Core Network Exposure Function, Oracle Communications Cloud Native Core Policy, Redhat Enterprise Linux.

How do I fix CVE-2021-43389?

Apply the vendor's patch.

Is CVE-2021-43389 being exploited?

There is no known exploitation of CVE-2021-43389 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-6604, CVE-2021-3896, DEBIAN-CVE-2021-43389, GHSA-7pcx-9wjr-42p4, UBUNTU-CVE-2021-43389.