SB2026072111 - NULL pointer dereference in Linux kernel f2fs

Description

This security bulletin contains information about 1 vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2026-63811)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 6.8 [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]

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

The vulnerability exists due to a null pointer dereference in f2fs atomic write handling when reading COW data during write-begin processing. A local user can update an atomic-write file in a crafted encryption-policy state to cause a denial of service.

The issue occurs when the original inode and its COW inode use different encryption contexts, causing decryption to be attempted on a folio owned by the original inode.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/a41075acde0124d2f8a5f563068a5d63e8ffd57b
• https://git.kernel.org/stable/c/a92332f32a8d31a7eee47b1dc1d751cb3319908f