CVE-2021-43267
CRITICALEPSS 99th pctlDescription
An issue was discovered in net/tipc/crypto.c in the Linux kernel before 5.14.16. The Transparent Inter-Process Communication (TIPC) functionality allows remote attackers to exploit insufficient validation of user-supplied sizes for the MSG_CRYPTO message type.
How to fix
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This Ubuntu release reached end-of-life on 2025-05-31. Extended security maintenance is available until 2030-04-02.
This vulnerability affects an unusually large number of packages. The highest-confidence fixes are shown above; the full list is longer. Check the referenced advisories for complete coverage.
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploit Intelligence
Very high risk: more likely to be exploited than 99% of all known CVEs.
References
Related Vulnerabilities
Other CWE-1284 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2022-20699 | Critical | 10.0 | 72% | KEV | - |
| CVE-2022-31629 | Medium | 6.5 | 49% | - | Fix |
| CVE-2025-9316 | Medium | 6.9 | 36% | - | - |
| CVE-2022-36620 | High | 7.5 | 23% | - | - |
| CVE-2008-1440 | High | 7.1 | 23% | - | - |
| CVE-2022-37134 | Critical | 9.8 | 22% | - | - |
Common questions
How do I fix CVE-2021-43267?
Published advisories record a fix for 33 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.
Is CVE-2021-43267 being actively exploited?
Not that we know of. CVE-2021-43267 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 57.9% is the estimated probability that it will be exploited in the next 30 days. That is higher than 99% of all scored CVEs.
How severe is CVE-2021-43267?
CVE-2021-43267 has a CVSS v3 base score of 9.8, rated critical. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-43267 affect?
Published advisories record a fix for linux (Debian), linux-aws-5.11 (Ubuntu), linux-azure-5.11 (Ubuntu), linux-gcp-5.11 (Ubuntu), and 29 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-17.