SB20260502112 - Out-of-bounds read in Linux kernel tty vt driver

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds read (CVE-ID: CVE-2026-31742)

CWE-ID: CWE-125 - Out-of-bounds read

CVSSv4: 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

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to an out-of-bounds read in the virtual terminal unicode screen buffer handling when leaving the alternate screen after a console resize. A local user can trigger alternate screen transitions and resize the console to cause a kernel oops.

The issue occurs when a stale saved unicode buffer is restored after the console dimensions have changed, causing buffer iteration to use mismatched row and column dimensions.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/40014493cece72a0be5672cd86763e53fb3ec613
• https://git.kernel.org/stable/c/428fdf55301e6c8fa5a36b426240797b1cf86570
• https://git.kernel.org/stable/c/891d790fdb5c96c6e1d2841e06ee6c360f2d1288