CVE-2021-46992
netfilter: nftables: avoid overflows in nft_hash_buckets()
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nftables: avoid overflows in nft_hash_buckets() Number of buckets being stored in 32bit variables, we have to ensure that no overflows occur in nft_hash_buckets() syzbot injected a size == 0x40000000 and reported: UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13 shift exponent 64 is too large for 64-bit type 'long unsigned int' CPU: 1 PID: 29539 Comm: syz-executor.4 Not tainted 5.12.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327 __roundup_pow_of_two include/linux/log2.h:57 [inline] nft_hash_buckets net/netfilter/nft_set_hash.c:411 [inline] nft_hash_estimate.cold+0x19/0x1e net/netfilter/nft_set_hash.c:652 nft_select_set_ops net/netfilter/nf_tables_api.c:3586 [inline] nf_tables_newset+0xe62/0x3110 net/netfilter/nf_tables_api.c:4322 nfnetlink_rcv_batch+0xa09/0x24b0 net/netfilter/nfnetlink.c:488 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:612 [inline] nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:630 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1927 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2350 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.26% · top 82% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Weakness
Affected products
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < 2824cafc6a93792d9ad85939c499161214d84c4b
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < efcd730ddd6f25578bd31bfe703e593e2421d708
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < c77e2ef18167ad334e27610ced9a7f6af5ec1787
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < 72b49dd116ca00a46a11d5a4d8d7987f05ed9cd7
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < 1e8ab479cfbe5751efccedb95afb9b112a5ba475
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < a388d10961ff8578b1a6691945d406c0f33aa71b
- affected 0ed6389c483dc77cdbdd48de0ca7ce41723dd667 – < a54754ec9891830ba548e2010c889e3c8146e449
- affected 4.9
- unaffected < 4.9
- unaffected 4.14.233 – ≤ 4.14.*
- unaffected 4.19.191 – ≤ 4.19.*
- unaffected 5.4.120 – ≤ 5.4.*
- unaffected 5.10.38 – ≤ 5.10.*
- unaffected 5.11.22 – ≤ 5.11.*
- unaffected 5.12.5 – ≤ 5.12.*
- unaffected 5.13 – ≤ *
References (7)
- https://git.kernel.org/stable/c/2824cafc6a93792d9ad85939c499161214d84c4b (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/efcd730ddd6f25578bd31bfe703e593e2421d708 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/c77e2ef18167ad334e27610ced9a7f6af5ec1787 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/72b49dd116ca00a46a11d5a4d8d7987f05ed9cd7 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/1e8ab479cfbe5751efccedb95afb9b112a5ba475 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/a388d10961ff8578b1a6691945d406c0f33aa71b (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/a54754ec9891830ba548e2010c889e3c8146e449 (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-46992)Record last updated .