Google: sys-kernel/cchost-kernel-6_18, sys-kernel/csql-kernel-6_18, sys-kernel/lakitu-kernel-6_18, sys-kernel/lakitu-nc-kernel-6_18: security update to 20198.0.0

high Tenable Cloud Security Plugin ID 475804

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

- In the Linux kernel, the following vulnerability has been resolved: smb/client: flush dirty data before
punching a hole Punching a hole after a large buffered write may leave the range reported as data.
Reproduce it with: xfs_io -f \ -c "pwrite -b 3m -S 0x61 0 3m" \ -c "fpunch 1m 1m" \ -c "seek -h 0" \ -c
"seek -d 1m" \ /mnt/test/repro Punching 1 MiB at offset 1 MiB should produce: 0 1 MiB 2 MiB 3 MiB | DATA |
HOLE | DATA | EOF Instead, the entire file is reported as data. SEEK_HOLE(0) returns EOF, and
SEEK_DATA(1M) returns 1M. This happens because a dirty folio spanning the punched range can be written
back after the punch and refill the hole. Fix this by flushing and waiting for dirty data in the punched
range before invalidating the page cache and issuing FSCTL_SET_ZERO_DATA. The xfstests generic/539 pass
against Samba/ksmbd with this change. (CVE-2026-93794)

Solution

Update the sys-kernel/cchost-kernel-6_18 library and its related packages to version 20198.0.0 or later.

See Also

https://storage.googleapis.com/cos-oval-vulnerability-feed/cos-138.oval.xml.tar.gz

Plugin Details

Severity: High

ID: 475804

Version: Revision 1.1

Type: Local

Published: 10/16/2026

Updated: 10/16/2026

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.45

Vendor

Vendor Severity: LOW

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-93794

CVSS v3

Risk Factor: High

Base Score: 7.1

Temporal Score: 6.2

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 9/24/2026

Reference Information

CVE: CVE-2026-93794