7.8

CVE-2021-46992: netfilter: nftables: avoid overflows in nft_hash_buckets()

Modified
AliasesUBUNTU-CVE-2021-46992DEBIAN-CVE-2021-46992
Published 28-02-2024Last modified 05-08-2026

Vulnerability summary

CVE-2021-46992 is a high (CVSS 7.8) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 18.1% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.26%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 6 · Related 6
SUSE-SU-2024:0925-1SUSE-SU-2024:0975-1SUSE-SU-2024:0976-1SUSE-SU-2024:1454-1SUSE-SU-2024:1465-1SUSE-SU-2024:1489-1

Timeline

  1. 28-02-2024
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

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

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

18%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.26% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu85 products
  • linux< 4.15.0-151.157 | < 5.4.0-80.90
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.15.0-1109.116 | < 5.4.0-1054.57
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < 2824cafc6a93792d9ad85939c499161214d84c4b | ≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < efcd730ddd6f25578bd31bfe703e593e2421d708 | ≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < c77e2ef18167ad334e27610ced9a7f6af5ec1787 | ≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < 72b49dd116ca00a46a11d5a4d8d7987f05ed9cd7 | ≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < 1e8ab479cfbe5751efccedb95afb9b112a5ba475 | ≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < a388d10961ff8578b1a6691945d406c0f33aa71b | ≥ 0ed6389c483dc77cdbdd48de0ca7ce41723dd667, < a54754ec9891830ba548e2010c889e3c8146e449 | 4.9
  • linux_kernel≥ 4.9, < 4.14.233 | ≥ 4.15, < 4.19.191 | ≥ 4.20, < 5.4.120 | ≥ 5.5, < 5.10.38 | ≥ 5.11, < 5.11.22 | ≥ 5.12, < 5.12.5
Debian1 product
  • linux< 5.10.38-1

3 vendors · 88 products

References

11 links
Show all 11 references