CVE-2024-26641

CVE Details

Release Date:

2024-03-18

Description

In the Linux kernel, the following vulnerability has been resolved:\nip6_tunnel: make sure to pull inner header in __ip6_tnl_rcv()\nsyzbot found __ip6_tnl_rcv() could access unitiliazed data [1].\nCall pskb_inet_may_pull() to fix this, and initialize ipv6h\nvariable after this call as it can change skb->head.\n[1]\nBUG: KMSAN: uninit-value in __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]\nBUG: KMSAN: uninit-value in INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]\nBUG: KMSAN: uninit-value in IP6_ECN_decapsulate+0x7df/0x1e50 include/net/inet_ecn.h:321\n__INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]\nINET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]\nIP6_ECN_decapsulate+0x7df/0x1e50 include/net/inet_ecn.h:321\nip6ip6_dscp_ecn_decapsulate+0x178/0x1b0 net/ipv6/ip6_tunnel.c:727\n__ip6_tnl_rcv+0xd4e/0x1590 net/ipv6/ip6_tunnel.c:845\nip6_tnl_rcv+0xce/0x100 net/ipv6/ip6_tunnel.c:888\ngre_rcv+0x143f/0x1870\nip6_protocol_deliver_rcu+0xda6/0x2a60 net/ipv6/ip6_input.c:438\nip6_input_finish net/ipv6/ip6_input.c:483 [inline]\nNF_HOOK include/linux/netfilter.h:314 [inline]\nip6_input+0x15d/0x430 net/ipv6/ip6_input.c:492\nip6_mc_input+0xa7e/0xc80 net/ipv6/ip6_input.c:586\ndst_input include/net/dst.h:461 [inline]\nip6_rcv_finish+0x5db/0x870 net/ipv6/ip6_input.c:79\nNF_HOOK include/linux/netfilter.h:314 [inline]\nipv6_rcv+0xda/0x390 net/ipv6/ip6_input.c:310\n__netif_receive_skb_one_core net/core/dev.c:5532 [inline]\n__netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5646\nnetif_receive_skb_internal net/core/dev.c:5732 [inline]\nnetif_receive_skb+0x58/0x660 net/core/dev.c:5791\ntun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1555\ntun_get_user+0x53af/0x66d0 drivers/net/tun.c:2002\ntun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048\ncall_write_iter include/linux/fs.h:2084 [inline]\nnew_sync_write fs/read_write.c:497 [inline]\nvfs_write+0x786/0x1200 fs/read_write.c:590\nksys_write+0x20f/0x4c0 fs/read_write.c:643\n__do_sys_write fs/read_write.c:655 [inline]\n__se_sys_write fs/read_write.c:652 [inline]\n__x64_sys_write+0x93/0xd0 fs/read_write.c:652\ndo_syscall_x64 arch/x86/entry/common.c:52 [inline]\ndo_syscall_64+0x6d/0x140 arch/x86/entry/common.c:83\nentry_SYSCALL_64_after_hwframe+0x63/0x6b\nUninit was created at:\nslab_post_alloc_hook+0x129/0xa70 mm/slab.h:768\nslab_alloc_node mm/slub.c:3478 [inline]\nkmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523\nkmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560\n__alloc_skb+0x318/0x740 net/core/skbuff.c:651\nalloc_skb include/linux/skbuff.h:1286 [inline]\nalloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6334\nsock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2787\ntun_alloc_skb drivers/net/tun.c:1531 [inline]\ntun_get_user+0x1e8a/0x66d0 drivers/net/tun.c:1846\ntun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048\ncall_write_iter include/linux/fs.h:2084 [inline]\nnew_sync_write fs/read_write.c:497 [inline]\nvfs_write+0x786/0x1200 fs/read_write.c:590\nksys_write+0x20f/0x4c0 fs/read_write.c:643\n__do_sys_write fs/read_write.c:655 [inline]\n__se_sys_write fs/read_write.c:652 [inline]\n__x64_sys_write+0x93/0xd0 fs/read_write.c:652\ndo_syscall_x64 arch/x86/entry/common.c:52 [inline]\ndo_syscall_64+0x6d/0x140 arch/x86/entry/common.c:83\nentry_SYSCALL_64_after_hwframe+0x63/0x6b\nCPU: 0 PID: 5034 Comm: syz-executor331 Not tainted 6.7.0-syzkaller-00562-g9f8413c4a66f #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023

See more information about CVE-2024-26641 from MITRE CVE dictionary and NIST NVD

CVSS Scoring

NOTE: The following CVSS v3.1 metrics and score provided are preliminary and subject to review.

Base Score:	5.5	CVSS Vector:	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector:	Local network	Attack Complexity:	Low
Privileges Required:	Low	User Interaction:	None
Scope:	Unchanged	Confidentiality Impact:	None
Integrity Impact:	None	Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (kernel)	ELSA-2024-9315	2024-11-14