What is CVE-2026-63899?

CVE-2026-63899 is a unscored severity Linux kernel vulnerability, affecting Linux kernel versions from 3.14 onward and patched in 5.10.259, 5.15.210, 6.1.176 and others. CVE-2026-63899 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-63899?

CVE-2026-63899 has a CVSS score of pending NVD analysis out of 10, rated awaiting scoring severity.

Is there a patch available for CVE-2026-63899?

Yes, CVE-2026-63899 has been patched. Fixed versions include 5.10.259, 5.15.210, 6.1.176 and others. If you are running Linux kernel 3.14 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-63899 actively exploited?

CVE-2026-63899 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-63899

In the Linux kernel, the following vulnerability has been resolved: USB: serial: mxuport: fix memory corruption with small endpoint Make sure that the bulk-out endpoint max packet size is at least eight bytes to avoid user-controlled slab corruption should a malicious device report a smaller size.

Package Linux Kernel

Published 2026-07-19

Last modified 2026-07-19

Patch available

Yes

Affected versions

Linux kernel versions 3.14 and later are affected. Fixed in 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.93, 6.18.35, 7.0.12, 7.1 and their respective stable series.

Affected from

≥ 3.14

Fixed in

✓ 5.10.259 5.10.x ✓ 5.15.210 5.15.x ✓ 6.1.176 6.1.x ✓ 6.6.143 6.6.x ✓ 6.12.93 6.12.x ✓ 6.18.35 6.18.x ✓ 7.0.12 7.0.x ✓ 7.1

References

8 total

Showing 5 of 8 references View all on NVD

Frequently asked questions

What is CVE-2026-63899?

CVE-2026-63899 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 3.14 onward and has been patched in 5.10.259, 5.15.210, 6.1.176 and others. CVE-2026-63899 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
Is there a patch available for CVE-2026-63899?

Yes — CVE-2026-63899 has been patched. Fixed versions include 5.10.259, 5.15.210, 6.1.176 and others. If you are running Linux kernel 3.14 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-63899 actively exploited?

No — CVE-2026-63899 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.