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 472731

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: md: do overflow check for
sb->bblog_shift in super_1_load() In super_1_load(), sb->bblog_shift is an __u8 type value loaded from on-
disk superblock. It is used for badblocks API badblocks_set() by the following sequence, 1930
rdev->badblocks.shift = sb->bblog_shift; 1931 for (i = 0 ; i < (sectors << (9-3)) ; i++, bbp++) { 1932 u64
bb = le64_to_cpu(*bbp); 1933 int count = bb & (0x3ff); 1934 u64 sector = bb >> 10; 1935 sector <<=
sb->bblog_shift; 1936 count <<= sb->bblog_shift; 1937 if (bb + 1 == 0) 1938 break; 1939 if
(!badblocks_set(&rdev->badblocks, sector, count, 1)) 1940 return -EINVAL; 1941 } bb->bblog_shit is in
range of 0-255, variable sector is 64bit width, for an invalid bb->bblog_shit, it is possible to make
sector be overflowed by the following calculation, 1935 sector <<= sb->bblog_shift; Then in turn when call
badblocks_set() at line 1939 with the invalid rdev->badblocks.shift set at line 1930, may result an
overflow inside _badblocks_clear() in block/badblocks.c. Although there are many places to call badblocks
APIs, the non-zero shift value is only used in super_1_load(), other places always use 0 as the shift
value. Therefore it is unnecessary to do a general shift value overflow check inside badblock API, and
just check here as the caller. This may avoid unnecessary check, make the badblocks API code more simple
and elegant. (CVE-2026-89557)

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: 472731

Version: Revision 1.2

Type: Local

Family: Google COS Security Checks

Published: 10/5/2026

Updated: 10/6/2026

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

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.27

Vendor

Vendor Severity: LOW

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

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

CVSS Score Source: CVE-2026-89557

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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: 9/11/2026

Reference Information

CVE: CVE-2026-89557

Detections

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