Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2021-47129— netfilter: nft_ct: skip expectations for confirmed conntrack

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel 存在安全漏洞，该漏洞源于 netfilter 模块中存在错误。

CVSS 7.8 · High EPSS 0.45% · P37

Affected Version Matrix 10

VendorProduct Version RangeStatus
Linux Linux 857b46027d6f91150797295752581b7155b9d0e1< da8d31e80ff425f5a65dab7060d5c4aba749e562 affected
857b46027d6f91150797295752581b7155b9d0e1< 5f3429c05e4028a0e241afdad856dd15dec2ffb9 affected
857b46027d6f91150797295752581b7155b9d0e1< 2c0e6b35b88a961127066a1028bce9c727cbc3e5 affected
857b46027d6f91150797295752581b7155b9d0e1< 1710eb913bdcda3917f44d383c32de6bdabfc836 affected
5.3 affected
< 5.3 unaffected
5.4.125≤ 5.4.* unaffected
5.10.43≤ 5.10.* unaffected
… +2 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2021-47129

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
netfilter: nft_ct: skip expectations for confirmed conntrack
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: skip expectations for confirmed conntrack nft_ct_expect_obj_eval() calls nf_ct_ext_add() for a confirmed conntrack entry. However, nf_ct_ext_add() can only be called for !nf_ct_is_confirmed(). [ 1825.349056] WARNING: CPU: 0 PID: 1279 at net/netfilter/nf_conntrack_extend.c:48 nf_ct_xt_add+0x18e/0x1a0 [nf_conntrack] [ 1825.351391] RIP: 0010:nf_ct_ext_add+0x18e/0x1a0 [nf_conntrack] [ 1825.351493] Code: 41 5c 41 5d 41 5e 41 5f c3 41 bc 0a 00 00 00 e9 15 ff ff ff ba 09 00 00 00 31 f6 4c 89 ff e8 69 6c 3d e9 eb 96 45 31 ed eb cd <0f> 0b e9 b1 fe ff ff e8 86 79 14 e9 eb bf 0f 1f 40 00 0f 1f 44 00 [ 1825.351721] RSP: 0018:ffffc90002e1f1e8 EFLAGS: 00010202 [ 1825.351790] RAX: 000000000000000e RBX: ffff88814f5783c0 RCX: ffffffffc0e4f887 [ 1825.351881] RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88814f578440 [ 1825.351971] RBP: 0000000000000000 R08: 0000000000000000 R09: ffff88814f578447 [ 1825.352060] R10: ffffed1029eaf088 R11: 0000000000000001 R12: ffff88814f578440 [ 1825.352150] R13: ffff8882053f3a00 R14: 0000000000000000 R15: 0000000000000a20 [ 1825.352240] FS: 00007f992261c900(0000) GS:ffff889faec00000(0000) knlGS:0000000000000000 [ 1825.352343] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1825.352417] CR2: 000056070a4d1158 CR3: 000000015efe0000 CR4: 0000000000350ee0 [ 1825.352508] Call Trace: [ 1825.352544] nf_ct_helper_ext_add+0x10/0x60 [nf_conntrack] [ 1825.352641] nft_ct_expect_obj_eval+0x1b8/0x1e0 [nft_ct] [ 1825.352716] nft_do_chain+0x232/0x850 [nf_tables] Add the ct helper extension only for unconfirmed conntrack. Skip rule evaluation if the ct helper extension does not exist. Thus, you can only create expectations from the first packet. It should be possible to remove this limitation by adding a new action to attach a generic ct helper to the first packet. Then, use this ct helper extension from follow up packets to create the ct expectation. While at it, add a missing check to skip the template conntrack too and remove check for IPCT_UNTRACK which is implicit to !ct.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel 存在安全漏洞，该漏洞源于 netfilter 模块中存在错误。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux 857b46027d6f91150797295752581b7155b9d0e1 ~ da8d31e80ff425f5a65dab7060d5c4aba749e562 -
Linux Linux 5.3 -

II. Public POCs for CVE-2021-47129

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2021-47129

请登录查看更多情报信息。

Other References for CVE-2021-47129 (4)

Same Patch Batch · Linux · 2024-03-15 · 26 CVEs total

CVE-2021-47111 8.8 HIGH xen-netback: take a reference to the RX task thread
CVE-2021-47131 8.1 HIGH net/tls: Fix use-after-free after the TLS device goes down and up
CVE-2021-47135 7.8 HIGH mt76: mt7921: fix possible AOOB issue in mt7921_mcu_tx_rate_report
CVE-2021-47112 7.8 HIGH x86/kvm: Teardown PV features on boot CPU as well
CVE-2021-47123 7.8 HIGH io_uring: fix ltout double free on completion race
CVE-2021-47124 7.8 HIGH io_uring: fix link timeout refs
CVE-2021-47126 7.8 HIGH ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
CVE-2021-47132 7.5 HIGH mptcp: fix sk_forward_memory corruption on retransmission
CVE-2021-47130 7.5 HIGH nvmet: fix freeing unallocated p2pmem
CVE-2021-47109 7.5 HIGH neighbour: allow NUD_NOARP entries to be forced GCed
CVE-2021-47113 7.1 HIGH btrfs: abort in rename_exchange if we fail to insert the second ref
CVE-2021-47122 net: caif: fix memory leak in caif_device_notify
CVE-2021-47134 efi/fdt: fix panic when no valid fdt found
CVE-2021-47133 HID: amd_sfh: Fix memory leak in amd_sfh_work
CVE-2021-47128 bpf, lockdown, audit: Fix buggy SELinux lockdown permission checks
CVE-2021-47127 ice: track AF_XDP ZC enabled queues in bitmap
CVE-2021-47125 sch_htb: fix refcount leak in htb_parent_to_leaf_offload
CVE-2021-47121 net: caif: fix memory leak in cfusbl_device_notify
CVE-2021-47120 HID: magicmouse: fix NULL-deref on disconnect
CVE-2021-47119 ext4: fix memory leak in ext4_fill_super

Showing top 20 of 26 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2021-47129

No comments yet

Leave a comment