Linux Kernel up to 6.1.102/6.6.43/6.10.2 apparmor_socket_post_create null pointer dereference

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.1.102/6.6.43/6.10.2. Affected by this issue is the function apparmor_socket_post_create. Such manipulation leads to null pointer dereference. This vulnerability is uniquely identified as CVE-2023-52889. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.102/6.6.43/6.10.2. It has been rated as critical. Affected by this issue is the function apparmor_socket_post_create. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: apparmor: Fix null pointer deref when receiving skb during sock creation The panic below is observed when receiving ICMP packets with secmark set while an ICMP raw socket is being created. SK_CTX(sk)->label is updated in apparmor_socket_post_create(), but the packet is delivered to the socket before that, causing the null pointer dereference. Drop the packet if label context is not set. BUG: kernel NULL pointer dereference, address: 000000000000004c #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 407 Comm: a.out Not tainted 6.4.12-arch1-1 #1 3e6fa2753a2d75925c34ecb78e22e85a65d083df Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/28/2020 RIP: 0010:aa_label_next_confined+0xb/0x40 Code: 00 00 48 89 ef e8 d5 25 0c 00 e9 66 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 0f 1f 44 00 00 89 f0 77 4c 39 c6 7e 1f 48 63 d0 48 8d 14 d7 eb 0b 83 c0 01 48 83 c2 RSP: 0018:ffffa92940003b08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000000e RDX: ffffa92940003be8 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8b57471e7800 R08: ffff8b574c642400 R09: 0000000000000002 R10: ffffffffbd820eeb R11: ffffffffbeb7ff00 R12: ffff8b574c642400 R13: 0000000000000001 R14: 0000000000000001 R15: 0000000000000000 FS: 00007fb092ea7640(0000) GS:ffff8b577bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000004c CR3: 00000001020f2005 CR4: 00000000007706f0 PKRU: 55555554 Call Trace: ? __die+0x23/0x70 ? page_fault_oops+0x171/0x4e0 ? exc_page_fault+0x7f/0x180 ? asm_exc_page_fault+0x26/0x30 ? aa_label_next_confined+0xb/0x40 apparmor_secmark_check+0xec/0x330 security_sock_rcv_skb+0x35/0x50 sk_filter_trim_cap+0x47/0x250 sock_queue_rcv_skb_reason+0x20/0x60 raw_rcv+0x13c/0x210 raw_local_deliver+0x1f3/0x250 ip_protocol_deliver_rcu+0x4f/0x2f0 ip_local_deliver_finish+0x76/0xa0 __netif_receive_skb_one_core+0x89/0xa0 netif_receive_skb+0x119/0x170 ? __netdev_alloc_skb+0x3d/0x140 vmxnet3_rq_rx_complete+0xb23/0x1010 [vmxnet3 56a84f9c97178c57a43a24ec073b45a9d6f01f3a] vmxnet3_poll_rx_only+0x36/0xb0 [vmxnet3 56a84f9c97178c57a43a24ec073b45a9d6f01f3a] __napi_poll+0x28/0x1b0 net_rx_action+0x2a4/0x380 __do_softirq+0xd1/0x2c8 __irq_exit_rcu+0xbb/0xf0 common_interrupt+0x86/0xa0 asm_common_interrupt+0x26/0x40 RIP: 0010:apparmor_socket_post_create+0xb/0x200 Code: 08 48 85 ff 75 a1 eb b1 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 41 54 48 89 fd 53 45 85 c0 0f 84 b2 00 00 00 48 8b 1d 80 56 3f 02 48 RSP: 0018:ffffa92940ce7e50 EFLAGS: 00000286 RAX: ffffffffbc756440 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000003 RSI: 0000000000000002 RDI: ffff8b574eaab740 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffff8b57444cec70 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000002 R14: ffff8b574eaab740 R15: ffffffffbd8e4748 ? __pfx_apparmor_socket_post_create+0x10/0x10 security_socket_post_create+0x4b/0x80 __sock_create+0x176/0x1f0 __sys_socket+0x89/0x100 __x64_sys_socket+0x17/0x20 do_syscall_64+0x5d/0x90 ? do_syscall_64+0x6c/0x90 ? do_syscall_64+0x6c/0x90 ? do_syscall_64+0x6c/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2023-52889 since 05/21/2024. The exploitation is known to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 207884 (openSUSE 15 Security Update : kernel (SUSE-SU-2024:3483-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.103, 6.6.44 or 6.10.3 eliminates this vulnerability. Applying the patch ead2ad1d9f04/6c920754f62c/46c17ead5b73/fce09ea31450 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (207884) and CERT Bund (WID-SEC-2024-1875). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• IBM Security Guardium
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Open Source Linux Kernel
• IBM QRadar SIEM
• IBM Spectrum Protect Plus
• SolarWinds Security Event Manager
• IBM DataPower Gateway
• Dell NetWorker

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.102
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.10.0
• 6.10.1
• 6.10.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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