Review reviewHigh

CVE-2025-40054

Linux

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix UAF issue in f2fs_merge_page_bio() As JY reported in bugzilla [1], Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 pc : [0xffffffe51d249484] f2fs_is_cp_guaranteed+0x70/0x98 lr : [0xffffffe51d24adbc] f2fs_merge_page_bio+0x520/0x6d4 CPU: 3 UID: 0 PID: 6790 Comm: kworker/u16:3 Tainted: P B W OE 6.12.30-android16-5-maybe-dirty-4k #1 5f7701c9cbf727d1eebe77c89bbbeb3371e895e5 Tainted: [P]=PROPRIETARY_MODULE, [B]=BAD_PAGE, [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Workqueue: writeb...

CVSS: 7.8
EPSS: 0.14%
CISA KEV: Not listed
Published: 2025.10.28

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.14%

Technical severityCVSS 7.8

Vulnerability overview

Affected product and versions

Product: Linux
Affected versions: >= 0b20fcec8651569935a10afe03fedc0b812d044e < 01118321e0c8a5f3ece57d0d377bfc92d83cd210, >= 0b20fcec8651569935a10afe03fedc0b812d044e < edf7e9040fc52c922db947f9c6c36f07377c52ea, >= 5.5
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Linux and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE: Not available