Detections
Analytics

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 19506.299.3

medium Tenable Self-Hosted Container Security Plugin ID 469573

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: xfrm: move policy_bydst RCU sync from
 per-netns .exit to .pre_exit The struct pernet_operations docstring in include/net/net_namespace.h
 explicitly warns against blocking RCU primitives in .exit handlers: Exit methods using blocking RCU
 primitives, such as synchronize_rcu(), should be implemented via exit_batch. [...] Please, avoid
 synchronize_rcu() at all, where it's possible. Note that a combination of pre_exit() and exit() can be
 used, since a synchronize_rcu() is guaranteed between the calls. xfrm_policy_fini() violates this: it
 calls synchronize_rcu() before freeing the policy_bydst hash tables (so no RCU reader is mid- traversal at
 free time), but runs from xfrm_net_ops.exit -- once per namespace -- so a cleanup_net() of N namespaces
 pays N full RCU grace periods serially. Use the documented pre_exit/exit split. Move the policy flush (and
 the workqueue drains it depends on) into a new .pre_exit handler; xfrm_policy_fini() then runs in .exit
 and frees the hash tables after the synchronize_rcu_expedited() that cleanup_net() guarantees between the
 two phases. Providing O(1) RCU grace periods per batch instead of O(N). Observed on Linux 6.18 with a
 workload doing unshare(CLONE_NEWNET) at ~13/sec sustained: cleanup_net() and the netns_wq rescuer kthread
 both stuck in xfrm_policy_fini()'s synchronize_rcu(), >300k struct net accumulated in the cleanup queue,
 Percpu in /proc/meminfo climbed to 130+ GB on 256-CPU hosts, and memcg OOMs followed. setup_net and
 __put_net counts were balanced, ruling out a refcount leak. (CVE-2026-64525)

Solution

Update the sys-kernel/cchost-kernel-6_12 library and its related packages to version 19506.299.3 or later.

See Also

https://storage.googleapis.com/cos-oval-vulnerability-feed/cos-129.oval.xml.tar.gz

Plugin Details

Severity: Medium

ID: 469573

Version: Revision 1.6

Type: Local

Published: 10/3/2026

Updated: 10/6/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.59

Vendor

Vendor Severity: LOW

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

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

CVSS Score Source: CVE-2026-64525

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/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: 6/22/2026

Reference Information

CVE: CVE-2026-64525