CVE-2025-68366 Affecting kernel-tools package, versions *


Severity

Recommended
low

Based on CentOS security rating.

Threat Intelligence

EPSS
0.02% (6th percentile)

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  • Snyk IDSNYK-CENTOS8-KERNELTOOLS-14720179
  • published26 Dec 2025
  • disclosed24 Dec 2025

Introduced: 24 Dec 2025

NewCVE-2025-68366  (opens in a new tab)

How to fix?

There is no fixed version for Centos:8 kernel-tools.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-tools package and not the kernel-tools package as distributed by Centos. See How to fix? for Centos:8 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

nbd: defer config unlock in nbd_genl_connect

There is one use-after-free warning when running NBD_CMD_CONNECT and NBD_CLEAR_SOCK:

nbd_genl_connect nbd_alloc_and_init_config // config_refs=1 nbd_start_device // config_refs=2 set NBD_RT_HAS_CONFIG_REF open nbd // config_refs=3 recv_work done // config_refs=2 NBD_CLEAR_SOCK // config_refs=1 close nbd // config_refs=0 refcount_inc -> uaf

------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 24 PID: 1014 at lib/refcount.c:25 refcount_warn_saturate+0x12e/0x290 nbd_genl_connect+0x16d0/0x1ab0 genl_family_rcv_msg_doit+0x1f3/0x310 genl_rcv_msg+0x44a/0x790

The issue can be easily reproduced by adding a small delay before refcount_inc(&nbd->config_refs) in nbd_genl_connect():

    mutex_unlock(&nbd->config_lock);
    if (!ret) {
            set_bit(NBD_RT_HAS_CONFIG_REF, &config->runtime_flags);
  •           printk("before sleep\n");
    
  •           mdelay(5 * 1000);
    
  •           printk("after sleep\n");
              refcount_inc(&nbd->config_refs);
              nbd_connect_reply(info, nbd->index);
      }
    

CVSS Base Scores

version 3.1