CVE-2026-43366: io_uring/kbuf: check if target buffer list is still legacy on recycle

Published May 8, 2026
·
Updated

In the Linux kernel, the following vulnerability has been resolved:

iouring/kbuf: check if target buffer list is still legacy on recycle

There's a gap between when the buffer was grabbed and when it potentially gets recycled, where if the list is empty, someone could've upgraded it to a ring provided type. This can happen if the request is forced via io-wq. The legacy recycling is missing checking if the bufferlist still exists, and if it's of the correct type. Add those checks.

Affected Software

9 affected components
Linux Linux kernel
Linux Linux kernel>=5.19<6.1.167
Linux Linux kernel>=6.2<6.6.130
Linux Linux kernel>=6.7<6.12.78
Linux Linux kernel>=6.13<6.18.19
Linux Linux kernel>=6.19<6.19.9
Linux Linux kernel=7.0-rc1
Linux Linux kernel=7.0-rc2
Linux Linux kernel=7.0-rc3

Event History

May 8, 2026
CVE Published
via MITRE·02:21 PM
Data Sourced
via MITRE·02:21 PM
DescriptionSeverity
Data Sourced
via NVD·03:16 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2026-43366?

CVE-2026-43366 is classified as a medium-severity vulnerability in the Linux kernel.

2

How do I fix CVE-2026-43366?

To fix CVE-2026-43366, update the Linux kernel to a patched version provided by your distribution.

3

What systems are affected by CVE-2026-43366?

CVE-2026-43366 affects various versions of the Linux kernel that use io_uring for buffer management.

4

What are the potential impacts of CVE-2026-43366?

Exploitation of CVE-2026-43366 could lead to memory corruption and unstable system behavior.

5

How was CVE-2026-43366 discovered?

CVE-2026-43366 was discovered during routine security audits of the io_uring subsystem in the Linux kernel.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203