Google: sys-kernel/cchost-kernel-6_12, sys-kernel/csql-kernel-6_12, sys-kernel/lakitu-kernel-6_12, sys-kernel/lakitu-nc-kernel-6_12: security update to 19506.505.8

high Tenable Cloud Security Plugin ID 472104

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: ext4: check dir entry fits before
reading the hash trailer in ext4_search_dir() For casefolded encrypted directories ext4 stores an 8-byte
hash trailer after the name (EXT4_DIRENT_HASHES()), at an offset derived from de->name_len. On the
sb_no_casefold_compat_fallback() path ext4_match() reads that trailer, but ext4_search_dir()'s by-hand
pre-check only tests de->name + de->name_len <= dlimit, which proves the name fits, not the rounded
trailer. A crafted entry whose name ends at the block boundary passes the check while
EXT4_DIRENT_HASHES(de) lands past the block end, so ext4_match() reads out of bounds on an ordinary
lookup. KASAN reports it as a use-after-free when the page after the directory block holds a freed object:
BUG: KASAN: use-after-free in ext4_match (fs/ext4/namei.c:1435) Read of size 4 at addr ffff888010458000 by
task exploit Call Trace: ext4_match (fs/ext4/namei.c:1435) ext4_search_dir (fs/ext4/namei.c:1470)
__ext4_find_entry (fs/ext4/namei.c:1268 fs/ext4/namei.c:1632) ext4_lookup (fs/ext4/namei.c:1703
fs/ext4/namei.c:1769) ... filename_lookup (fs/namei.c:2842) vfs_statx (fs/stat.c:353) __do_sys_newfstatat
(fs/stat.c:538) do_syscall_64 (arch/x86/entry/syscall_64.c:94) entry_SYSCALL_64_after_hwframe
(arch/x86/entry/entry_64.S:121) Require, for hash-in-dirent directories, that the whole entry including
the rounded trailer fits before calling ext4_match(). This is the same bound ext4_check_dir_entry()
already enforces via ext4_dir_rec_len(), so no well-formed entry is rejected. The other caller,
ext4_find_dest_de(), runs ext4_check_dir_entry() first and is unaffected. (CVE-2026-89787)

Solution

Update the sys-kernel/cchost-kernel-6_12 library and its related packages to version 19506.505.8 or later.

Plugin Details

Severity: High

ID: 472104

Version: Revision 1.2

Type: Local

Family: Google COS Security Checks

Published: 10/3/2026

Updated: 10/3/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Medium

Score: 4.3

Percentile: 53.39

Vendor

Vendor Severity: LOW

CVSS v2

Risk Factor: Medium

Base Score: 5.4

Temporal Score: 4

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

CVSS Score Source: CVE-2026-89787

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:H/I:N/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: 9/16/2026

Reference Information

CVE: CVE-2026-89787

Detections

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