CVE-2021-47129
published 2024-03-15CVE-2021-47129: In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: skip expectations for confirmed conntrack nft_ct_expect_obj_eval() calls…
PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.45%
38.5th percentile
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 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 m
Affected
17 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.10.46-1 (bookworm) | linux 5.10.46-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 857b46027d6f91150797295752581b7155b9d0e1 < da8d31e80ff425f5a65dab7060d5c4aba749e562 | da8d31e80ff425f5a65dab7060d5c4aba749e562 |
| linux | linux | >= 857b46027d6f91150797295752581b7155b9d0e1 < 5f3429c05e4028a0e241afdad856dd15dec2ffb9 | 5f3429c05e4028a0e241afdad856dd15dec2ffb9 |
| linux | linux | >= 857b46027d6f91150797295752581b7155b9d0e1 < 2c0e6b35b88a961127066a1028bce9c727cbc3e5 | 2c0e6b35b88a961127066a1028bce9c727cbc3e5 |
| linux | linux | >= 857b46027d6f91150797295752581b7155b9d0e1 < 1710eb913bdcda3917f44d383c32de6bdabfc836 | 1710eb913bdcda3917f44d383c32de6bdabfc836 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.46-1 | 5.10.46-1 |
| linux | linux_kernel | >= 0 < 5.10.46-1 | 5.10.46-1 |
| linux | linux_kernel | >= 0 < 5.10.46-1 | 5.10.46-1 |
| linux | linux_kernel | >= 0 < 5.10.46-1 | 5.10.46-1 |
| linux | linux_kernel | >= 5.11 < 5.12.10 | 5.12.10 |
| linux | linux_kernel | >= 5.3 < 5.4.125 | 5.4.125 |
| linux | linux_kernel | >= 5.5 < 5.10.43 | 5.10.43 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv4.6MEDIUM
vendor_debian4.6MEDIUM
vendor_redhat4.6MEDIUM
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VulDB
Linux Kernel up to 5.4.124/5.10.42/5.12.9 Netfilter nf_conntrack_extend.c nft_ct_expect_obj_eval dropped privileges (Nessus ID 239742)
vuldb·2026-08-05·CVSS 7.8
CVE-2021-47129 [HIGH] Linux Kernel up to 5.4.124/5.10.42/5.12.9 Netfilter nf_conntrack_extend.c nft_ct_expect_obj_eval dropped privileges (Nessus ID 239742)
A vulnerability identified as problematic has been detected in Linux Kernel up to 5.4.124/5.10.42/5.12.9. This vulnerability affects the function nft_ct_expect_obj_eval of the file net/netfilter/nf_conntrack_extend.c of the component Netfilter. Performing a manipulation results in improper check for dropped privileges.
This vulnerability is reported as CVE-2021-47129. The attacker must have access to the local network to execute the attack. No exploit exists.
You should upgrade the affected component.
OSV
CVE-2021-47129: In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: skip expectations for confirmed conntrack nft_ct_expect_obj_eva
osv·2024-03-15·CVSS 4.6
CVE-2021-47129 [MEDIUM] CVE-2021-47129: In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_ct: skip expectations for confirmed conntrack nft_ct_expect_obj_eva
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 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
GHSA
GHSA-w7x4-qp38-gw56: In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_ct: skip expectations for confirmed conntrack
nft_ct_expect_obj_e
ghsa_unreviewed·2024-03-15
CVE-2021-47129 [MEDIUM] CWE-273 GHSA-w7x4-qp38-gw56: In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_ct: skip expectations for confirmed conntrack
nft_ct_expect_obj_e
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 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
Red Hat
kernel: netfilter: nft_ct: skip expectations for confirmed conntrack
vendor_redhat·2024-03-15·CVSS 4.6
CVE-2021-47129 [MEDIUM] CWE-20 kernel: netfilter: nft_ct: skip expectations for confirmed conntrack
kernel: netfilter: nft_ct: skip expectations for confirmed conntrack
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 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: 0
Debian
CVE-2021-47129: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
vendor_debian·2021·CVSS 4.6
CVE-2021-47129 [MEDIUM] CVE-2021-47129: linux - In the Linux kernel, the following vulnerability has been resolved: netfilter: ...
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 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
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/1710eb913bdcda3917f44d383c32de6bdabfc836https://git.kernel.org/stable/c/2c0e6b35b88a961127066a1028bce9c727cbc3e5https://git.kernel.org/stable/c/5f3429c05e4028a0e241afdad856dd15dec2ffb9https://git.kernel.org/stable/c/da8d31e80ff425f5a65dab7060d5c4aba749e562https://git.kernel.org/stable/c/1710eb913bdcda3917f44d383c32de6bdabfc836https://git.kernel.org/stable/c/2c0e6b35b88a961127066a1028bce9c727cbc3e5https://git.kernel.org/stable/c/5f3429c05e4028a0e241afdad856dd15dec2ffb9https://git.kernel.org/stable/c/da8d31e80ff425f5a65dab7060d5c4aba749e562
2024-03-15
Published