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 19506.224.80

critical Tenable Cloud Security Plugin ID 469820

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: gve: fix header buffer corruption with
header-split and HW-GRO The DQO RX datapath programs a per-buffer-queue-descriptor header_buf_addr at post
time and reads the split header back at completion time. Both the post and the read currently index the
header buffer by queue position rather than by the buffer's identity: - post (gve_rx_post_buffers_dqo):
header_buf_addr is computed from bufq->tail - read (gve_rx_dqo): the header is read from desc_idx (the
completion queue head index) This relies on the buffer-queue index and the completion-queue index being
equal for the start of every packet, i.e. on the device consuming posted buffers and returning completions
in the exact same order. That assumption does not hold once HW-GRO is enabled with multiple flows:
coalesced segments are accepted and completed in an order that may differ from the order buffers were
posted, and segments from different flows may interleave. That results in two problems: 1. Wrong header
slot on read. Because the read offset is derived from the completion index (desc_idx) while the device
wrote the header to the address programmed for the buffer's buf_id, the driver can copy a header belonging
to a different packet. This shows up as throughput drop (about 30% drop and large numbers of TCP
retransmissions) with header-split and HW-GRO both enabled and many streams. 2. Header buffer reused while
still owned by the device. The driver advances bufq->head by one per completion and re-posts buffers based
on that. Arrival of N RX completions only guarantees that at least N RX buffer descriptors have been read
by the device. It does not guarantee that the device has relinquished the ownership of all the buffers
corresponding to those N descriptors. With out-of-order completions (e.g. the completion for a packet
copied into buffer N arrives before the completion for a packet copied into buffer N-1), the driver can
re-post and overwrite a header buffer that the device is still going to write into, corrupting the header
of a packet whose completion has not yet been processed. Fix both issues by indexing the header buffer by
buf_id on both the post and read paths. Reading from buf_id's slot is therefore always correct regardless
of completion ordering (fixes problem 1). Indexing by buf_id also ties each header slot to the lifetime of
its buffer state. A buffer state is only returned to the free/recycle lists when its own completion
(buf_id) is processed, so its header slot can only be re-posted after the device is done with it. This
makes header slot reuse safe under out-of-order completions (fixes problem 2). Allocate
(gve_rx_alloc_hdr_bufs) and free (gve_rx_free_hdr_bufs) the header buffers based on num_buf_states to
match the buf_id indexing. (CVE-2026-72046)

Solution

Update the sys-kernel/cchost-kernel-6_12 library and its related packages to version 19506.224.80 or later.

Plugin Details

Severity: Critical

ID: 469820

Version: Revision 1.6

Type: Local

Family: Google COS Security Checks

Published: 10/3/2026

Updated: 10/6/2026

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

Risk Information

VPR

Risk Factor: High

Score: 7.6

Percentile: 98.3

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-2026-72046

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-2026-72046

Detections

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