SB2026052886 - Out-of-bounds write in Linux kernel mm

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds write (CVE-ID: CVE-2026-45990)

CWE-ID: CWE-787 - Out-of-bounds write

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 write in krealloc() and kvrealloc() fallback paths when shrinking an object while forcing a new alignment or NUMA migration. A local user can trigger a reallocation with crafted size and alignment parameters to cause a denial of service.

The issue can also result in zero-byte copying during NUMA migration in the reallocation path.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/082a6d03a2d685a83a332666b500ad3966349588
• https://git.kernel.org/stable/c/38387ccc0fbe38d14fb4c2ad7ee1d7404e5e59fd
• https://git.kernel.org/stable/c/550fa6b5aabb096554536ac1e3ec96b76cbb35fd