Google: sys-kernel/csql-kernel-6_1, sys-kernel/csql-kernel-6_6, sys-kernel/lakitu-kernel-6_1, sys-kernel/lakitu-kernel-6_6, sys-kernel/lakitu-nc-kernel-6_6, sys-kernel/lakitu-vgpu-kernel-6_6, sys-kernel/tpusev-kernel-6_6: security update to 18613.731.2

critical Tenable Cloud Security Plugin ID 466374

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: ipv4: igmp: Fix potential UAF in
igmp_gq_start_timer() A race condition exists between device teardown (inetdev_destroy) and incoming IGMP
query processing (igmp_rcv), leading to a Use-After-Free in the IGMP timer callback. During device
destruction, inetdev_destroy() drops the primary reference to in_device, which can drop its refcount to 0.
The actual freeing of in_device memory is deferred via RCU (using call_rcu()). Concurrently, igmp_rcv()
runs under RCU read lock and obtains the in_device pointer. Because the memory is RCU-protected, CPU-0 can
safely dereference in_device even if its refcount has hit 0. However, if CPU-0 calls igmp_gq_start_timer()
and re-arms the timer, it attempts to acquire a reference using in_dev_hold(). This increments the
refcount from 0 to 1, triggering a "refcount_t: addition on 0" warning. Since the in_device memory is
still scheduled to be freed after the RCU grace period (as the free callback does not check the refcount
again), the device is freed while the timer is still armed. When the timer expires, it accesses the freed
memory, causing a kernel panic. Fix this by using refcount_inc_not_zero() (via a new helper
in_dev_hold_safe()) to prevent acquiring a reference if the device is already being destroyed. If the
refcount is 0, we do not arm the timer. A similar issue in IPv6 MLD is fixed in a subsequent patch.
(CVE-2026-72323)

Solution

Update the sys-kernel/csql-kernel-6_1 library and its related packages to version 18613.731.2 or later.

Plugin Details

Severity: Critical

ID: 466374

Version: Revision 1.1

Type: Local

Family: Google COS Security Checks

Published: 10/2/2026

Updated: 10/2/2026

Risk Information

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.29

Vendor

Vendor Severity: LOW

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

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

CVSS Score Source: CVE-2026-72323

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/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: 8/11/2026

Reference Information

CVE: CVE-2026-72323

Detections

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