Cloudanix VulnDB

CVE-2024-47692

Medium · 6.5

CVSS

6.5

EPSS

1.2%

Published

Oct 21, 2024

CISA due date

—

Cloudanix analysis

Schedule a fix SSVC: Track

A flaw in the Linux NFS server can cause the whole system to crash when a special tracking file becomes corrupted, interrupting file sharing until the server is restarted or updated.

Exploitation
Remote Authenticated
Attacker needs
Low Privilege
Complexity
Moderate
Impact
Denial Of Service
Component
OS kernel
Class
Memory Corruption
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Null pointer dereference in nfs4_client_to_reclaim triggered when memdup_user receives namelen=0 and returns ZERO_SIZE_PTR from a corrupted /var/lib/nfs/nfsdcld/main.sqlite.

Why it matters to the business

Kernel panic or process crash in NFS server environments can cause denial of service, disrupting file sharing services and requiring manual recovery or reboot.

How an attack unfolds

An attacker or misconfiguration corrupts the nfsdcld SQLite database so that a subsequent downcall supplies namelen=0; the kernel assigns ZERO_SIZE_PTR to name.data and later dereferences it inside nfs4_client_to_reclaim during reclaim processing.

How to fix it

Update the Linux kernel to commit 6d07040ae5c2214e39c7444d898039c9e655a79a or later stable release containing the namelen==0 check; ensure /var/lib/nfs/nfsdcld/main.sqlite is recreated from a clean state after upgrade.

How to confirm the fix worked

Confirm the patch is present by checking the nfsd source for the namelen==0 early return before memdup_user; attempt to reproduce the zero-length name condition in a test environment and verify no dereference occurs.

Typical attack path

  1. Corrupt or replace /var/lib/nfs/nfsdcld/main.sqlite with entries that yield namelen=0
  2. Trigger nfsdcld to perform a downcall via rpc_pipe_write
  3. nfsd processes the reclaim record and calls nfs4_client_to_reclaim
  4. KASAN reports null-ptr-deref and the kernel oops or panics

How to detect it

Search kernel logs for KASAN null-ptr-deref reports containing nfs4_client_to_reclaim and cld_pipe_downcall; inspect nfsdcld process crashes and unexpected restarts of the nfsdcld daemon.

What your security team should do

  • Prioritize kernel upgrade on all systems exposing NFSv4 services
  • Monitor for nfsdcld or kernel crashes referencing nfs4_client_to_reclaim
  • Validate database integrity of nfsdcld SQLite files during maintenance windows
  • Apply the fix across all supported stable branches before the next scheduled reboot cycle

The record

In the Linux kernel, the following vulnerability has been resolved: nfsd: return -EINVAL when namelen is 0 When we have a corrupted main.sqlite in /var/lib/nfs/nfsdcld/, it may result in namelen being 0, which will cause memdup_user() to return ZERO_SIZE_PTR. When we access the name.data that has been assigned the value of ZERO_SIZE_PTR in nfs4_client_to_reclaim(), null pointer dereference is triggered. [ T1205] ================================================================== [ T1205] BUG: KASAN: null-ptr-deref in nfs4_client_to_reclaim+0xe9/0x260 [ T1205] Read of size 1 at addr 0000000000000010 by task nfsdcld/1205 [ T1205] [ T1205] CPU: 11 PID: 1205 Comm: nfsdcld Not tainted 5.10.0-00003-g2c1423731b8d #406 [ T1205] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014 [ T1205] Call Trace: [ T1205] dump_stack+0x9a/0xd0 [ T1205] ? nfs4_client_to_reclaim+0xe9/0x260 [ T1205] __kasan_report.cold+0x34/0x84 [ T1205] ? nfs4_client_to_reclaim+0xe9/0x260 [ T1205] kasan_report+0x3a/0x50 [ T1205] nfs4_client_to_reclaim+0xe9/0x260 [ T1205] ? nfsd4_release_lockowner+0x410/0x410 [ T1205] cld_pipe_downcall+0x5ca/0x760 [ T1205] ? nfsd4_cld_tracking_exit+0x1d0/0x1d0 [ T1205] ? down_write_killable_nested+0x170/0x170 [ T1205] ? avc_policy_seqno+0x28/0x40 [ T1205] ? selinux_file_permission+0x1b4/0x1e0 [ T1205] rpc_pipe_write+0x84/0xb0 [ T1205] vfs_write+0x143/0x520 [ T1205] ksys_write+0xc9/0x170 [ T1205] ? __ia32_sys_read+0x50/0x50 [ T1205] ? ktime_get_coarse_real_ts64+0xfe/0x110 [ T1205] ? ktime_get_coarse_real_ts64+0xa2/0x110 [ T1205] do_syscall_64+0x33/0x40 [ T1205] entry_SYSCALL_64_after_hwframe+0x67/0xd1 [ T1205] RIP: 0033:0x7fdbdb761bc7 [ T1205] Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 514 [ T1205] RSP: 002b:00007fff8c4b7248 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ T1205] RAX: ffffffffffffffda RBX: 000000000000042b RCX: 00007fdbdb761bc7 [ T1205] RDX: 000000000000042b RSI: 00007fff8c4b75f0 RDI: 0000000000000008 [ T1205] RBP: 00007fdbdb761bb0 R08: 0000000000000000 R09: 0000000000000001 [ T1205] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000042b [ T1205] R13: 0000000000000008 R14: 00007fff8c4b75f0 R15: 0000000000000000 [ T1205] ================================================================== Fix it by checking namelen.

Affected packages

Ecosystem Package Introduced Fixed
Debian:11 linux 0 No fix
Debian:11 linux 0 5.10.234-1
Debian:11 linux-6.1 0 6.1.119-1~deb11u1
Debian:12 linux 0 No fix
Debian:13 linux 0 6.11.2-1
Linux Kernel 5.2.0 5.4.285
Mageia:9 kernel 0 6.6.58-2.mga9
Mageia:9 kernel-firmware 0 20240909-1.mga9
Mageia:9 kernel-firmware-nonfree 0 20240909-1.mga9.nonfree
Mageia:9 kernel-linus 0 6.6.58-2.mga9
Mageia:9 kmod-virtualbox 0 7.0.20-57.mga9
Mageia:9 kmod-xtables-addons 0 3.24-65.mga9
Mageia:9 radeon-firmware 0 20240909-1.mga9.nonfree
SUSE:Linux Enterprise High Availability Extension 15 SP5 kernel-default 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise High Availability Extension 15 SP6 kernel-default 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Live Patching 15 SP5 kernel-default 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Live Patching 15 SP5 kernel-livepatch-SLE15-SP5-RT_Update_22 0 1-150500.11.3.1
SUSE:Linux Enterprise Live Patching 15 SP5 kernel-livepatch-SLE15-SP5_Update_21 0 1-150500.11.5.1
SUSE:Linux Enterprise Live Patching 15 SP6 kernel-default 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Live Patching 15 SP6 kernel-livepatch-SLE15-SP6-RT_Update_5 0 1-150600.1.3.1
SUSE:Linux Enterprise Live Patching 15 SP6 kernel-livepatch-SLE15-SP6_Update_6 0 1-150600.13.3.5
SUSE:Linux Enterprise Micro 5.5 kernel-default 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Micro 5.5 kernel-default-base 0 5.14.21-150500.55.88.1.150500.6.39.4
SUSE:Linux Enterprise Micro 5.5 kernel-rt 0 5.14.21-150500.13.76.1
SUSE:Linux Enterprise Micro 5.5 kernel-source-rt 0 5.14.21-150500.13.76.1
SUSE:Linux Enterprise Module for Basesystem 15 SP5 kernel-64kb 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Basesystem 15 SP5 kernel-default 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Basesystem 15 SP5 kernel-default-base 0 5.14.21-150500.55.88.1.150500.6.39.4
SUSE:Linux Enterprise Module for Basesystem 15 SP5 kernel-source 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Basesystem 15 SP5 kernel-zfcpdump 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-64kb 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-default 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-default-base 0 6.4.0-150600.23.30.1.150600.12.12.6
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-source 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Basesystem 15 SP6 kernel-zfcpdump 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-coco 0 6.4.0-15061.9.coco15sp6.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-coco_debug 0 6.4.0-15061.9.coco15sp6.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-source-coco 0 6.4.0-15061.9.coco15sp6.1
SUSE:Linux Enterprise Module for Confidential Computing Technical Preview 15 SP6 kernel-syms-coco 0 6.4.0-15061.9.coco15sp6.1
SUSE:Linux Enterprise Module for Development Tools 15 SP5 kernel-docs 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Development Tools 15 SP5 kernel-obs-build 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Development Tools 15 SP5 kernel-source 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Development Tools 15 SP5 kernel-syms 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-docs 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-obs-build 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-source 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Development Tools 15 SP6 kernel-syms 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Legacy 15 SP5 kernel-default 0 5.14.21-150500.55.88.1
SUSE:Linux Enterprise Module for Legacy 15 SP6 kernel-default 0 6.4.0-150600.23.30.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP5 kernel-azure 0 5.14.21-150500.33.72.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP5 kernel-source-azure 0 5.14.21-150500.33.72.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP5 kernel-syms-azure 0 5.14.21-150500.33.72.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP6 kernel-azure 0 6.4.0-150600.8.17.2
SUSE:Linux Enterprise Module for Public Cloud 15 SP6 kernel-source-azure 0 6.4.0-150600.8.17.1
SUSE:Linux Enterprise Module for Public Cloud 15 SP6 kernel-syms-azure 0 6.4.0-150600.8.17.1
SUSE:Linux Enterprise Workstation Extension 15 SP6 kernel-default 0 6.4.0-150600.23.30.1
SUSE:Real Time Module 15 SP5 kernel-rt 0 5.14.21-150500.13.76.1
SUSE:Real Time Module 15 SP5 kernel-rt_debug 0 5.14.21-150500.13.76.1
SUSE:Real Time Module 15 SP5 kernel-source-rt 0 5.14.21-150500.13.76.1
SUSE:Real Time Module 15 SP5 kernel-syms-rt 0 5.14.21-150500.13.76.1
SUSE:Real Time Module 15 SP6 kernel-rt 0 6.4.0-150600.10.17.1
SUSE:Real Time Module 15 SP6 kernel-rt_debug 0 6.4.0-150600.10.17.1
SUSE:Real Time Module 15 SP6 kernel-source-rt 0 6.4.0-150600.10.17.1
SUSE:Real Time Module 15 SP6 kernel-syms-rt 0 6.4.0-150600.10.17.1
Ubuntu:14.04:LTS linux 0 3.11.0-12.19
Ubuntu:14.04:LTS linux-aws 0 4.4.0-1002.2
Ubuntu:14.04:LTS linux-azure 0 4.15.0-1023.24~14.04.1
Ubuntu:14.04:LTS linux-lts-xenial 0 4.4.0-13.29~14.04.1
Ubuntu:16.04:LTS linux 0 4.4.0-2.16
Ubuntu:16.04:LTS linux-aws 0 4.4.0-1001.10
Ubuntu:16.04:LTS linux-aws-hwe 0 4.15.0-1030.31~16.04.1
Ubuntu:16.04:LTS linux-azure 0 4.11.0-1009.9
Ubuntu:16.04:LTS linux-gcp 0 4.10.0-1004.4
Ubuntu:16.04:LTS linux-hwe 0 4.8.0-39.42~16.04.1
Ubuntu:16.04:LTS linux-hwe-edge 0 No fix
Ubuntu:16.04:LTS linux-kvm 0 4.4.0-1004.9
Ubuntu:16.04:LTS linux-oracle 0 4.15.0-1007.9~16.04.1
Ubuntu:18.04:LTS linux 0 4.13.0-16.19
Ubuntu:18.04:LTS linux-aws 0 4.15.0-1001.1
Ubuntu:18.04:LTS linux-aws-5.0 0 No fix
Ubuntu:18.04:LTS linux-aws-5.3 0 No fix
Ubuntu:18.04:LTS linux-azure 0 No fix
Ubuntu:18.04:LTS linux-azure-4.15 0 4.15.0-1082.92
Ubuntu:18.04:LTS linux-azure-5.3 0 No fix
Ubuntu:18.04:LTS linux-azure-edge 0 No fix
Ubuntu:18.04:LTS linux-gcp 0 No fix
Ubuntu:18.04:LTS linux-gcp-4.15 0 4.15.0-1071.81
Ubuntu:18.04:LTS linux-gcp-5.3 0 No fix
Ubuntu:18.04:LTS linux-gke-4.15 0 No fix
Ubuntu:18.04:LTS linux-gke-5.4 0 No fix
Ubuntu:18.04:LTS linux-gkeop-5.4 0 No fix
Ubuntu:18.04:LTS linux-hwe 0 No fix
Ubuntu:18.04:LTS linux-hwe-edge 0 No fix
Ubuntu:18.04:LTS linux-kvm 0 4.15.0-1002.2
Ubuntu:18.04:LTS linux-oem 0 No fix
Ubuntu:18.04:LTS linux-oracle 0 4.15.0-1007.9
Ubuntu:18.04:LTS linux-oracle-5.0 0 No fix
Ubuntu:18.04:LTS linux-oracle-5.3 0 No fix
Ubuntu:20.04:LTS linux 0 No fix
Ubuntu:20.04:LTS linux 0 5.4.0-208.228
Ubuntu:20.04:LTS linux-aws 0 No fix
Ubuntu:20.04:LTS linux-aws 0 5.4.0-1140.150
Ubuntu:20.04:LTS linux-aws-5.11 0 No fix
Ubuntu:20.04:LTS linux-aws-5.13 0 No fix
Ubuntu:20.04:LTS linux-aws-5.15 0 5.15.0-1073.79~20.04.1
Ubuntu:20.04:LTS linux-aws-5.8 0 No fix
Ubuntu:20.04:LTS linux-azure 0 No fix
Ubuntu:20.04:LTS linux-azure 0 5.4.0-1145.152
Ubuntu:20.04:LTS linux-azure-5.11 0 No fix
Ubuntu:20.04:LTS linux-azure-5.13 0 No fix
Ubuntu:20.04:LTS linux-azure-5.15 0 5.15.0-1078.87~20.04.1
Ubuntu:20.04:LTS linux-azure-5.8 0 No fix
Ubuntu:20.04:LTS linux-azure-fde 0 No fix
Ubuntu:20.04:LTS linux-azure-fde-5.15 0 No fix
Ubuntu:20.04:LTS linux-bluefield 0 No fix
Ubuntu:20.04:LTS linux-bluefield 0 5.4.0-1099.106
Ubuntu:20.04:LTS linux-gcp 0 No fix
Ubuntu:20.04:LTS linux-gcp 0 5.4.0-1143.152
Ubuntu:20.04:LTS linux-gcp-5.11 0 No fix
Ubuntu:20.04:LTS linux-gcp-5.13 0 No fix
Ubuntu:20.04:LTS linux-gcp-5.15 0 5.15.0-1072.80~20.04.1
Ubuntu:20.04:LTS linux-gcp-5.8 0 No fix
Ubuntu:20.04:LTS linux-gke 0 No fix
Ubuntu:20.04:LTS linux-gke-5.15 0 No fix
Ubuntu:20.04:LTS linux-gkeop 0 No fix
Ubuntu:20.04:LTS linux-gkeop-5.15 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.11 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.13 0 No fix
Ubuntu:20.04:LTS linux-hwe-5.15 0 5.15.0-127.137~20.04.1
Ubuntu:20.04:LTS linux-hwe-5.8 0 No fix
Ubuntu:20.04:LTS linux-ibm 0 No fix
Ubuntu:20.04:LTS linux-ibm 0 5.4.0-1086.91
Ubuntu:20.04:LTS linux-ibm-5.15 0 5.15.0-1066.69~20.04.1
Ubuntu:20.04:LTS linux-intel-5.13 0 No fix
Ubuntu:20.04:LTS linux-intel-iotg-5.15 0 5.15.0-1071.77~20.04.1
Ubuntu:20.04:LTS linux-iot 0 No fix
Ubuntu:20.04:LTS linux-iot 0 5.4.0-1048.51
Ubuntu:20.04:LTS linux-kvm 0 No fix
Ubuntu:20.04:LTS linux-kvm 0 5.4.0-1127.136
Ubuntu:20.04:LTS linux-lowlatency-hwe-5.15 0 5.15.0-127.137~20.04.1
Ubuntu:20.04:LTS linux-nvidia-tegra-5.15 0 5.15.0-1032.32~20.04.1
Ubuntu:20.04:LTS linux-oem-5.10 0 No fix
Ubuntu:20.04:LTS linux-oem-5.13 0 No fix
Ubuntu:20.04:LTS linux-oem-5.14 0 No fix
Ubuntu:20.04:LTS linux-oem-5.6 0 No fix
Ubuntu:20.04:LTS linux-oracle 0 No fix
Ubuntu:20.04:LTS linux-oracle 0 5.4.0-1138.147
Ubuntu:20.04:LTS linux-oracle-5.11 0 No fix
Ubuntu:20.04:LTS linux-oracle-5.13 0 No fix
Ubuntu:20.04:LTS linux-oracle-5.15 0 5.15.0-1071.77~20.04.1
Ubuntu:20.04:LTS linux-oracle-5.8 0 No fix
Ubuntu:20.04:LTS linux-raspi 0 No fix
Ubuntu:20.04:LTS linux-raspi 0 5.4.0-1129.142
Ubuntu:20.04:LTS linux-raspi2 0 No fix
Ubuntu:20.04:LTS linux-riscv 0 No fix
Ubuntu:20.04:LTS linux-riscv-5.11 0 No fix
Ubuntu:20.04:LTS linux-riscv-5.15 0 5.15.0-1069.73~20.04.1
Ubuntu:20.04:LTS linux-riscv-5.8 0 No fix
Ubuntu:20.04:LTS linux-xilinx-zynqmp 0 No fix
Ubuntu:20.04:LTS linux-xilinx-zynqmp 0 5.4.0-1058.62
Ubuntu:22.04:LTS linux 0 5.15.0-127.137
Ubuntu:22.04:LTS linux-allwinner-5.19 0 No fix
Ubuntu:22.04:LTS linux-aws 0 5.15.0-1073.79
Ubuntu:22.04:LTS linux-aws-5.19 0 No fix
Ubuntu:22.04:LTS linux-aws-6.2 0 No fix
Ubuntu:22.04:LTS linux-aws-6.5 0 No fix
Ubuntu:22.04:LTS linux-aws-6.8 0 No fix
Ubuntu:22.04:LTS linux-aws-6.8 0 6.8.0-1023.25~22.04.1
Ubuntu:22.04:LTS linux-azure 0 5.15.0-1078.87
Ubuntu:22.04:LTS linux-azure-5.19 0 No fix
Ubuntu:22.04:LTS linux-azure-6.2 0 No fix
Ubuntu:22.04:LTS linux-azure-6.5 0 No fix
Ubuntu:22.04:LTS linux-azure-6.8 0 No fix
Ubuntu:22.04:LTS linux-azure-6.8 0 6.8.0-1025.30~22.04.1
Ubuntu:22.04:LTS linux-azure-fde 0 No fix
Ubuntu:22.04:LTS linux-azure-fde-5.19 0 No fix
Ubuntu:22.04:LTS linux-azure-fde-6.2 0 No fix
Ubuntu:22.04:LTS linux-gcp 0 5.15.0-1072.80
Ubuntu:22.04:LTS linux-gcp-5.19 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.2 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.5 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.8 0 No fix
Ubuntu:22.04:LTS linux-gcp-6.8 0 6.8.0-1024.26~22.04.1
Ubuntu:22.04:LTS linux-gke 0 5.15.0-1070.76
Ubuntu:22.04:LTS linux-gkeop 0 5.15.0-1056.63
Ubuntu:22.04:LTS linux-hwe-5.19 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.2 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.5 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.8 0 No fix
Ubuntu:22.04:LTS linux-hwe-6.8 0 6.8.0-57.59~22.04.1
Ubuntu:22.04:LTS linux-ibm 0 5.15.0-1066.69
Ubuntu:22.04:LTS linux-ibm-6.8 0 6.8.0-1023.23~22.04.1
Ubuntu:22.04:LTS linux-intel-iot-realtime 0 No fix
Ubuntu:22.04:LTS linux-intel-iotg 0 5.15.0-1071.77
Ubuntu:22.04:LTS linux-kvm 0 5.15.0-1070.75
Ubuntu:22.04:LTS linux-lowlatency 0 5.15.0-127.137
Ubuntu:22.04:LTS linux-lowlatency-hwe-5.19 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.2 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.5 0 No fix
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.8 0 No fix

Related vulnerabilities