Cloudanix VulnDB

CVE-2024-26608

None

CVSS

—

EPSS

0.2%

Published

Mar 11, 2024

CISA due date

—

Cloudanix analysis

Monitor only SSVC: Track

A bug in the Linux kernel's built-in file sharing code could let a local user peek at internal memory or crash the system, fixed by a routine kernel update.

Exploitation
Local Privilege
Attacker needs
Local User
Complexity
Moderate
Impact
Data Exposure
Component
OS kernel
Class
Memory Corruption
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

Global out-of-bounds read in ksmbd_nl_policy during netlink attribute validation, allowing kernel memory read past the policy array bounds via malformed genetlink messages.

Why it matters to the business

Kernel information disclosure or potential denial of service on systems running the in-kernel SMB server; low immediate risk but requires kernel update across Linux distributions.

How an attack unfolds

An attacker with local access sends a crafted netlink message targeting the ksmbd family that references an out-of-range event type, triggering the bounds check failure in __nla_validate_parse and reading uninitialized kernel memory.

How to fix it

Apply the upstream fix that introduces __KSMBD_EVENT_MAX placeholder and adjusts KSMBD_EVENT_MAX usage; update to kernel commit aaa1f1a2ee80888c12ae2783f3a0be10e14067c5 or later stable releases containing the patch.

How to confirm the fix worked

Confirm the ksmbd_nl_policy array ends with the new placeholder entry and KSMBD_EVENT_MAX equals its predecessor; re-run the syzbot-style netlink fuzzer or inspect nlattr validation paths for the corrected bounds.

Typical attack path

  1. Obtain local code execution or user privileges on a Linux host with ksmbd enabled
  2. Construct a netlink genetlink message referencing KSMBD_EVENT_MAX or higher
  3. Send the message via netlink socket to trigger validate_nla on ksmbd_nl_policy
  4. Read leaked kernel memory from the OOB access or trigger KASAN panic

How to detect it

Inspect kernel logs for KASAN global-out-of-bounds reports referencing ksmbd_nl_policy or validate_nla; correlate with netlink sendmsg activity from untrusted processes.

  • KASAN: global-out-of-bounds in validate_nla.*ksmbd_nl_policy
  • BUG: KASAN: global-out-of-bounds in __nla_validate_parse

What your security team should do

  • Prioritize kernel updates on any system exposing ksmbd or accepting unprivileged netlink messages
  • Disable ksmbd module if SMB server functionality is not required
  • Monitor for new stable kernel releases containing the aaa1f1a2ee80888c12ae2783f3a0be10e14067c5 commit

The record

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix global oob in ksmbd_nl_policy Similar to a reported issue (check the commit b33fb5b801c6 ("net: qualcomm: rmnet: fix global oob in rmnet_policy"), my local fuzzer finds another global out-of-bounds read for policy ksmbd_nl_policy. See bug trace below: ================================================================== BUG: KASAN: global-out-of-bounds in validate_nla lib/nlattr.c:386 [inline] BUG: KASAN: global-out-of-bounds in __nla_validate_parse+0x24af/0x2750 lib/nlattr.c:600 Read of size 1 at addr ffffffff8f24b100 by task syz-executor.1/62810 CPU: 0 PID: 62810 Comm: syz-executor.1 Tainted: G N 6.1.0 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x172/0x475 mm/kasan/report.c:395 kasan_report+0xbb/0x1c0 mm/kasan/report.c:495 validate_nla lib/nlattr.c:386 [inline] __nla_validate_parse+0x24af/0x2750 lib/nlattr.c:600 __nla_parse+0x3e/0x50 lib/nlattr.c:697 __nlmsg_parse include/net/netlink.h:748 [inline] genl_family_rcv_msg_attrs_parse.constprop.0+0x1b0/0x290 net/netlink/genetlink.c:565 genl_family_rcv_msg_doit+0xda/0x330 net/netlink/genetlink.c:734 genl_family_rcv_msg net/netlink/genetlink.c:833 [inline] genl_rcv_msg+0x441/0x780 net/netlink/genetlink.c:850 netlink_rcv_skb+0x14f/0x410 net/netlink/af_netlink.c:2540 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x54e/0x800 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x930/0xe50 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0x154/0x190 net/socket.c:734 ____sys_sendmsg+0x6df/0x840 net/socket.c:2482 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2536 __sys_sendmsg+0xf3/0x1c0 net/socket.c:2565 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fdd66a8f359 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdd65e00168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fdd66bbcf80 RCX: 00007fdd66a8f359 RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000003 RBP: 00007fdd66ada493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc84b81aff R14: 00007fdd65e00300 R15: 0000000000022000 </TASK> The buggy address belongs to the variable: ksmbd_nl_policy+0x100/0xa80 The buggy address belongs to the physical page: page:0000000034f47940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ccc4b flags: 0x200000000001000(reserved|node=0|zone=2) raw: 0200000000001000 ffffea00073312c8 ffffea00073312c8 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffffffff8f24b000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffffff8f24b080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffffff8f24b100: f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 00 00 07 f9 ^ ffffffff8f24b180: f9 f9 f9 f9 00 05 f9 f9 f9 f9 f9 f9 00 00 00 05 ffffffff8f24b200: f9 f9 f9 f9 00 00 03 f9 f9 f9 f9 f9 00 00 04 f9 ================================================================== To fix it, add a placeholder named __KSMBD_EVENT_MAX and let KSMBD_EVENT_MAX to be its original value - 1 according to what other netlink families do. Also change two sites that refer the KSMBD_EVENT_MAX to correct value.

Affected packages

Ecosystem Package Introduced Fixed
Debian:12 linux 0 6.1.76-1
Debian:13 linux 0 6.6.15-1
Linux Kernel 5.1.0 5.15.149
Linux Kernel 5.15.0 5.15.149
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-aws-5.4 0 5.4.0-1018.18~18.04.1
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-5.4 0 5.4.0-1020.20~18.04.1
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-gcp-5.4 0 5.4.0-1019.19~18.04.2
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-5.4 0 5.4.0-37.41~18.04.1
Ubuntu:18.04:LTS linux-hwe-edge 0 5.0.0-15.16~18.04.1
Ubuntu:18.04:LTS linux-ibm-5.4 0 5.4.0-1010.11~18.04.2
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:18.04:LTS linux-oracle-5.4 0 5.4.0-1019.19~18.04.1
Ubuntu:18.04:LTS linux-raspi-5.4 0 5.4.0-1013.13~18.04.1
Ubuntu:20.04:LTS linux 0 5.4.0-9.12
Ubuntu:20.04:LTS linux-aws 0 5.4.0-1005.5
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 5.15.0-1061.67~20.04.1
Ubuntu:20.04:LTS linux-aws-5.8 0 No fix
Ubuntu:20.04:LTS linux-azure 0 5.4.0-1006.6
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 5.15.0-1063.72~20.04.1
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 5.15.0-1063.72~20.04.1.1
Ubuntu:20.04:LTS linux-bluefield 0 5.4.0-1007.10
Ubuntu:20.04:LTS linux-gcp 0 5.4.0-1005.5
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 5.15.0-1059.67~20.04.1
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 5.4.0-1008.9
Ubuntu:20.04:LTS linux-gkeop-5.15 0 5.15.0-1044.51~20.04.1
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 5.15.0-106.116~20.04.1
Ubuntu:20.04:LTS linux-hwe-5.8 0 No fix
Ubuntu:20.04:LTS linux-ibm 0 5.4.0-1003.4
Ubuntu:20.04:LTS linux-ibm-5.15 0 5.15.0-1054.57~20.04.1
Ubuntu:20.04:LTS linux-intel-5.13 0 No fix
Ubuntu:20.04:LTS linux-intel-iotg-5.15 0 5.15.0-1058.64~20.04.1
Ubuntu:20.04:LTS linux-iot 0 5.4.0-1001.3
Ubuntu:20.04:LTS linux-kvm 0 5.4.0-1004.4
Ubuntu:20.04:LTS linux-lowlatency-hwe-5.15 0 5.15.0-106.116~20.04.1
Ubuntu:20.04:LTS linux-nvidia-tegra-5.15 0 5.15.0-1027.27~20.04.1
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 5.4.0-1005.5
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 5.15.0-1059.65~20.04.1
Ubuntu:20.04:LTS linux-oracle-5.8 0 No fix
Ubuntu:20.04:LTS linux-raspi 0 5.4.0-1007.7
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 5.15.0-1057.61~20.04.1
Ubuntu:20.04:LTS linux-riscv-5.8 0 No fix
Ubuntu:20.04:LTS linux-xilinx-zynqmp 0 5.4.0-1020.24
Ubuntu:22.04:LTS linux 0 5.15.0-106.116
Ubuntu:22.04:LTS linux-allwinner-5.19 0 No fix
Ubuntu:22.04:LTS linux-aws 0 5.15.0-1061.67
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 6.8.0-1009.9~22.04.2
Ubuntu:22.04:LTS linux-azure 0 5.15.0-1063.72
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 6.5.0-1022.23~22.04.1
Ubuntu:22.04:LTS linux-azure-6.8 0 6.8.0-1008.8~22.04.1
Ubuntu:22.04:LTS linux-azure-fde 0 5.15.0-1063.72.1
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-azure-fde-6.8 0 No fix
Ubuntu:22.04:LTS linux-gcp 0 5.15.0-1059.67
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 6.5.0-1022.24~22.04.1
Ubuntu:22.04:LTS linux-gcp-6.8 0 6.8.0-1010.11~22.04.1
Ubuntu:22.04:LTS linux-gke 0 5.15.0-1058.63
Ubuntu:22.04:LTS linux-gkeop 0 5.15.0-1044.51
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 6.5.0-41.41~22.04.2
Ubuntu:22.04:LTS linux-hwe-6.8 0 6.8.0-38.38~22.04.1
Ubuntu:22.04:LTS linux-ibm 0 5.15.0-1054.57
Ubuntu:22.04:LTS linux-intel-iot-realtime 0 No fix
Ubuntu:22.04:LTS linux-intel-iotg 0 5.15.0-1057.63
Ubuntu:22.04:LTS linux-kvm 0 5.15.0-1058.63
Ubuntu:22.04:LTS linux-lowlatency 0 5.15.0-106.116
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 6.5.0-41.41.1~22.04.1
Ubuntu:22.04:LTS linux-lowlatency-hwe-6.8 0 6.8.0-38.38.1~22.04.2
Ubuntu:22.04:LTS linux-nvidia 0 5.15.0-1054.55
Ubuntu:22.04:LTS linux-nvidia-6.2 0 No fix
Ubuntu:22.04:LTS linux-nvidia-6.5 0 6.5.0-1021.22
Ubuntu:22.04:LTS linux-nvidia-6.8 0 6.8.0-1008.8~22.04.1
Ubuntu:22.04:LTS linux-nvidia-tegra 0 5.15.0-1026.26
Ubuntu:22.04:LTS linux-nvidia-tegra-igx 0 5.15.0-1015.15
Ubuntu:22.04:LTS linux-oem-5.17 0 No fix
Ubuntu:22.04:LTS linux-oem-6.0 0 No fix
Ubuntu:22.04:LTS linux-oem-6.1 0 No fix
Ubuntu:22.04:LTS linux-oem-6.5 0 6.5.0-1024.25
Ubuntu:22.04:LTS linux-oem-6.5 0 6.5.0-1022.23
Ubuntu:22.04:LTS linux-oracle 0 5.15.0-1059.65
Ubuntu:22.04:LTS linux-oracle-6.5 0 6.5.0-1024.24~22.04.1
Ubuntu:22.04:LTS linux-oracle-6.8 0 6.8.0-1006.6~22.04.3
Ubuntu:22.04:LTS linux-raspi 0 5.15.0-1054.57
Ubuntu:22.04:LTS linux-realtime 0 No fix
Ubuntu:22.04:LTS linux-riscv 0 No fix
Ubuntu:22.04:LTS linux-riscv-5.19 0 No fix
Ubuntu:22.04:LTS linux-riscv-6.5 0 6.5.0-40.40.1~22.04.1
Ubuntu:22.04:LTS linux-riscv-6.8 0 6.8.0-38.38.1~22.04.1
Ubuntu:22.04:LTS linux-starfive-5.19 0 No fix
Ubuntu:22.04:LTS linux-starfive-6.2 0 No fix
Ubuntu:22.04:LTS linux-starfive-6.5 0 6.5.0-1015.16~22.04.1
Ubuntu:22.04:LTS linux-xilinx-zynqmp 0 No fix
Ubuntu:22.04:LTS linux-xilinx-zynqmp 0 5.15.0-1030.34
Ubuntu:22.04:LTS:for:NVIDIA:BlueField linux-bluefield 0 No fix
Ubuntu:23.10 linux 0 6.5.0-41.41
Ubuntu:23.10 linux-aws 0 6.5.0-1021.21
Ubuntu:23.10 linux-azure 0 6.5.0-1022.23
Ubuntu:23.10 linux-gcp 0 6.5.0-1022.24
Ubuntu:23.10 linux-laptop 0 6.5.0-1017.20
Ubuntu:23.10 linux-lowlatency 0 6.5.0-41.41.1
Ubuntu:23.10 linux-oracle 0 6.5.0-1024.24
Ubuntu:23.10 linux-raspi 0 6.5.0-1018.21
Ubuntu:23.10 linux-starfive 0 6.5.0-1015.16
Ubuntu:24.04:LTS linux 0 6.8.0-11.11
Ubuntu:24.04:LTS linux-aws 0 6.8.0-1001.1
Ubuntu:24.04:LTS linux-azure 0 6.8.0-1001.1
Ubuntu:24.04:LTS linux-azure-fde 0 No fix
Ubuntu:24.04:LTS linux-gcp 0 6.8.0-1002.2
Ubuntu:24.04:LTS linux-gke 0 6.8.0-1003.5
Ubuntu:24.04:LTS linux-gkeop 0 6.8.0-1001.3
Ubuntu:24.04:LTS linux-ibm 0 6.8.0-1001.1
Ubuntu:24.04:LTS linux-lowlatency 0 6.8.0-7.7.1
Ubuntu:24.04:LTS linux-nvidia 0 6.8.0-1007.7
Ubuntu:24.04:LTS linux-nvidia-lowlatency 0 6.8.0-1009.9.1
Ubuntu:24.04:LTS linux-oem-6.11 0 6.11.0-1007.7
Ubuntu:24.04:LTS linux-oem-6.8 0 6.8.0-1003.3
Ubuntu:24.04:LTS linux-oracle 0 6.8.0-1001.1
Ubuntu:24.04:LTS linux-raspi 0 6.8.0-1001.1
Ubuntu:24.04:LTS linux-raspi-realtime 0 No fix
Ubuntu:24.04:LTS linux-realtime 0 6.8.0-1008.19
Ubuntu:24.04:LTS linux-riscv 0 6.8.0-20.20.1
Ubuntu:24.10 linux 0 6.8.0-31.31
Ubuntu:24.10 linux-aws 0 6.8.0-1008.8
Ubuntu:24.10 linux-azure 0 6.8.0-1007.7
Ubuntu:24.10 linux-gcp 0 6.8.0-1007.7
Ubuntu:24.10 linux-lowlatency 0 6.8.0-31.31.1
Ubuntu:24.10 linux-oracle 0 6.8.0-1005.5
Ubuntu:24.10 linux-raspi 0 6.8.0-1004.4
Ubuntu:24.10 linux-realtime 0 6.11.0-1001.1
Ubuntu:24.10 linux-riscv 0 6.8.0-31.31.1
Ubuntu:25.10 linux-azure-fde 0 No fix
Ubuntu:Nvidia-BlueField:22.04:LTS linux-bluefield 0 5.15.0-1043.45
Ubuntu:Pro:16.04:LTS linux-hwe-edge 0 No fix
Ubuntu:Pro:18.04:LTS linux-aws-5.0 0 No fix
Ubuntu:Pro:18.04:LTS linux-aws-5.3 0 No fix
Ubuntu:Pro:18.04:LTS linux-azure 0 No fix

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