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 469896

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: vfio/pci: clear vdev->msi_perm after
freeing it on init failure vfio_msi_cap_len() lazily allocates the per-device MSI permission table:
vdev->msi_perm = kmalloc_obj(struct perm_bits, GFP_KERNEL_ACCOUNT); if (!vdev->msi_perm) return -ENOMEM;
ret = init_pci_cap_msi_perm(vdev->msi_perm, len, flags); if (ret) { kfree(vdev->msi_perm); return ret; /*
vdev->msi_perm left dangling */ } When init_pci_cap_msi_perm() -> alloc_perm_bits() fails with -ENOMEM,
the error path frees vdev->msi_perm but leaves the freed pointer stored in it. vdev->msi_perm is not re-
zeroed later because struct vfio_pci_core_device is per-device and persists across open/close cycles, and
the vfio_config_init() error path returns without calling vfio_config_free(). So the dangling pointer
outlives the failed open. That leads to two use-after-frees on the same device: 1. Reuse. The next
vfio_config_init() sees the stale pointer at "if (vdev->msi_perm) return len;" and reuses the freed
object. MSI config accesses in vfio_pci_config_rw_single() then dereference and call the freed
perm->readfn / perm->writefn function pointers. 2. Double free. A later vfio_config_free() runs
free_perm_bits() and kfree() on the already-freed object. Fix it by NULLing vdev->msi_perm after the
kfree(), matching the NULL-after-free discipline already used in free_perm_bits() and vfio_config_free().
BUG: KASAN: slab-use-after-free in vfio_pci_config_rw_single (drivers/vfio/pci/vfio_pci_config.c:1961)
Read of size 8 at addr ffff88800fcc88d0 by task exploit/143 Call Trace: ... kasan_report
(mm/kasan/report.c:595) vfio_pci_config_rw_single (drivers/vfio/pci/vfio_pci_config.c:1961)
vfio_pci_config_rw (drivers/vfio/pci/vfio_pci_config.c:1986) vfio_pci_rw
(drivers/vfio/pci/vfio_pci_core.c:1599) vfs_read (fs/read_write.c:572) __x64_sys_pread64
(fs/read_write.c:764) do_syscall_64 (arch/x86/entry/syscall_64.c:94) ... Followed on device close by a
double free of the same object: Oops: general protection fault, probably for non-canonical address
0x1f63e0e8000008: 0000 [#1] SMP KASAN NOPTI RIP: 0010:kfree (mm/slub.c:6711) Call Trace: vfio_config_free
(drivers/vfio/pci/vfio_pci_config.c:1861) vfio_pci_core_disable (drivers/vfio/pci/vfio_pci_core.c:685)
vfio_pci_core_close_device (drivers/vfio/pci/vfio_pci_core.c:777) vfio_df_close
(drivers/vfio/vfio_main.c:602) vfio_device_fops_release (drivers/vfio/vfio_main.c:648) __fput
(fs/file_table.c:512) __x64_sys_close (fs/open.c:1496) do_syscall_64 (arch/x86/entry/syscall_64.c:94) ...
Kernel panic - not syncing: Fatal exception (CVE-2026-89777)

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: 469896

Version: Revision 1.5

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: Medium

Score: 5

Percentile: 93.17

Vendor

Vendor Severity: HIGH

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-2026-89777

CVSS v3

Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/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: 9/16/2026

Reference Information

CVE: CVE-2026-89777

Detections

Analytics