Linux Kernel up to 6.1.102/6.6.43/6.10.2 net/core/dev.c virtio_net_hdr_to_skb buffer overflow

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 vulnerability is the function virtio_net_hdr_to_skb of the file net/core/dev.c. The manipulation results in buffer overflow. This vulnerability is identified as CVE-2024-43817. There is not any exploit available. 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 classified as critical. Affected is the function virtio_net_hdr_to_skb of the file net/core/dev.c. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: missing check virtio Two missing check in virtio_net_hdr_to_skb() allowed syzbot to crash kernels again 1. After the skb_segment function the buffer may become non-linear (nr_frags != 0), but since the SKBTX_SHARED_FRAG flag is not set anywhere the __skb_linearize function will not be executed, then the buffer will remain non-linear. Then the condition (offset >= skb_headlen(skb)) becomes true, which causes WARN_ON_ONCE in skb_checksum_help. 2. The struct sk_buff and struct virtio_net_hdr members must be mathematically related. (gso_size) must be greater than (needed) otherwise WARN_ON_ONCE. (remainder) must be greater than (needed) otherwise WARN_ON_ONCE. (remainder) may be 0 if division is without remainder. offset+2 (4191) > skb_headlen() (1116) WARNING: CPU: 1 PID: 5084 at net/core/dev.c:3303 skb_checksum_help+0x5e2/0x740 net/core/dev.c:3303 Modules linked in: CPU: 1 PID: 5084 Comm: syz-executor336 Not tainted 6.7.0-rc3-syzkaller-00014-gdf60cee26a2e #0 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 RIP: 0010:skb_checksum_help+0x5e2/0x740 net/core/dev.c:3303 Code: 89 e8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 52 01 00 00 44 89 e2 2b 53 74 4c 89 ee 48 c7 c7 40 57 e9 8b e8 af 8f dd f8 90 0b 90 90 e9 87 fe ff ff e8 40 0f 6e f9 e9 4b fa ff ff 48 89 ef RSP: 0018:ffffc90003a9f338 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff888025125780 RCX: ffffffff814db209 RDX: ffff888015393b80 RSI: ffffffff814db216 RDI: 0000000000000001 RBP: ffff8880251257f4 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 000000000000045c R13: 000000000000105f R14: ffff8880251257f0 R15: 000000000000105d FS: 0000555555c24380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000f000 CR3: 0000000023151000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip_do_fragment+0xa1b/0x18b0 net/ipv4/ip_output.c:777 ip_fragment.constprop.0+0x161/0x230 net/ipv4/ip_output.c:584 ip_finish_output_gso net/ipv4/ip_output.c:286 [inline] __ip_finish_output net/ipv4/ip_output.c:308 [inline] __ip_finish_output+0x49c/0x650 net/ipv4/ip_output.c:295 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip_output+0x13b/0x2a0 net/ipv4/ip_output.c:433 dst_output include/net/dst.h:451 [inline] ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:129 iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82 ipip6_tunnel_xmit net/ipv6/sit.c:1034 [inline] sit_tunnel_xmit+0xed2/0x28f0 net/ipv6/sit.c:1076 __netdev_start_xmit include/linux/netdevice.h:4940 [inline] netdev_start_xmit include/linux/netdevice.h:4954 [inline] xmit_one net/core/dev.c:3545 [inline] dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3561 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4346 dev_queue_xmit include/linux/netdevice.h:3134 [inline] packet_xmit+0x257/0x380 net/packet/af_packet.c:276 packet_snd net/packet/af_packet.c:3087 [inline] packet_sendmsg+0x24ca/0x5240 net/packet/af_packet.c:3119 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2190 __do_sys_sendto net/socket.c:2202 [inline] __se_sys_sendto net/socket.c:2198 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2198 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Found by Linux Verification Center (linuxtesting.org) with Syzkaller

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2024-43817 since 08/17/2024. The exploitability is told to be easy. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 208906 (CBL Mariner 2.0 Security Update: kernel (CVE-2024-43817)), 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 5b1997487a3f/90d41ebe0cd4/e9164903b8b3/e269d79c7d35 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 (208906) 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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CVSSv4info

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CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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