Off-by-one in Linux kernel - CVE-2026-53306
Published: June 29, 2026
Vulnerability identifier: #VU135730
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-53306
CWE-ID: CWE-193
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an out-of-bounds read in hvc_iucv_get_private() in the hvc_iucv driver when handling a device index equal to the number of configured devices. A local user can trigger an off-by-one access to cause a denial of service.
The issue occurs because the bounds check permits access to hvc_iucv_table[8] when hvc_iucv_devices is 8.
How to mitigate CVE-2026-53306
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/11207e42a332eb8bbcb9fe74df9edd2a807c5607
- https://git.kernel.org/stable/c/3104a3f40feb107f77d7116ad9bf6c210ab7babf
- https://git.kernel.org/stable/c/3d3b89e6ab93bdd0efd45828bda6b0e61cc46dff
- https://git.kernel.org/stable/c/484357dff256c816d9466bda35eb765685e4dc86
- https://git.kernel.org/stable/c/a76511bc654819425d3b15e77b523d7f9d81f064
- https://git.kernel.org/stable/c/f1dc8e72de9aabe5d96767a4e97219ac26b79fe5
- https://git.kernel.org/stable/c/f2a880e802ad12d1e38039d1334fb1475d0f5241
- https://git.kernel.org/stable/c/fed8b8f33a46db0ee2efdb000f4f630c86ed8ca4