CVE-2026-43450

netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table()

HIGH
7.1
CVSS Score
Published: May 8, 2026 at 02:22 PM UTC
Updated: June 17, 2026 at 10:49 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.1
Exploit prediction
EPSS 0.1%

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_cthelper: fix OOB read in nfnl_cthelper_dump_table() nfnl_cthelper_dump_table() has a 'goto restart' that jumps to a label inside the for loop body. When the "last" helper saved in cb->args[1] is deleted between dump rounds, every entry fails the (cur != last) check, so cb->args[1] is never cleared. The for loop finishes with cb->args[0] == nf_ct_helper_hsize, and the 'goto restart' jumps back into the loop body bypassing the bounds check, causing an 8-byte out-of-bounds read on nf_ct_helper_hash[nf_ct_helper_hsize]. The 'goto restart' block was meant to re-traverse the current bucket when "last" is no longer found, but it was placed after the for loop instead of inside it. Move the block into the for loop body so that the restart only occurs while cb->args[0] is still within bounds. BUG: KASAN: slab-out-of-bounds in nfnl_cthelper_dump_table+0x9f/0x1b0 Read of size 8 at addr ffff888104ca3000 by task poc_cthelper/131 Call Trace: nfnl_cthelper_dump_table+0x9f/0x1b0 netlink_dump+0x333/0x880 netlink_recvmsg+0x3e2/0x4b0 sock_recvmsg+0xde/0xf0 __sys_recvfrom+0x150/0x200 __x64_sys_recvfrom+0x76/0x90 do_syscall_64+0xc3/0x6e0 Allocated by task 1: __kvmalloc_node_noprof+0x21b/0x700 nf_ct_alloc_hashtable+0x65/0xd0 nf_conntrack_helper_init+0x21/0x60 nf_conntrack_init_start+0x18d/0x300 nf_conntrack_standalone_init+0x12/0xc0

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.6 ≤ v < 5.10.2533.6 ≤ v < 5.15.2033.6 ≤ v < 6.1.1673.6 ≤ v < 6.12.783.6 ≤ v < 6.18.193.6 ≤ v < 6.19.93.6 ≤ v < 6.6.1303.6 ≤ v < 7.05.11 ≤ v < 5.15.2035.16 ≤ v < 6.1.1676.13 ≤ v < 6.18.196.19 ≤ v < 6.19.96.2 ≤ v < 6.6.1306.7 ≤ v < 6.12.7812f7a505331e6b2754684b509f2ac8f0011ce6443.67.0 rc17.0 rc27.0 rc3
Vendor states this is fixed in 05018cd9370f77bb18fbf6e15ff33c7a06f10b3c (fixed)
Vendor states this is fixed in 0605e1985a95d4334a67869aee45a47e82301abf (fixed)
Vendor states this is fixed in 3cc328ffc32ddb389cba7b78b6aa95d995c2876e (fixed)
Vendor states this is fixed in 4a1f6ee69267a5f524102c028981410eeacfa3da (fixed)
Vendor states this is fixed in 61b3a1f8621df1a5928118313f133996f6a786db (fixed)
Vendor states this is fixed in 6dcee8496d53165b2d8a5909b3050b62ae71fe89 (fixed)
Vendor states this is fixed in 894c5780ddadd5fde0e16f66587918e6be1504c4 (fixed)
Vendor states this is fixed in 92441f6d9405a0c18d03f278b395e782f79a4a30 (fixed)
Vendor states this is fixed in 3.6 (unaffected)
Vendor states this is fixed in 5.10.253 (unaffected)
Vendor states this is fixed in 5.15.203 (unaffected)
Vendor states this is fixed in 6.1.167 (unaffected)
Vendor states this is fixed in 6.12.78 (unaffected)
Vendor states this is fixed in 6.18.19 (unaffected)
Vendor states this is fixed in 6.19.9 (unaffected)
Vendor states this is fixed in 6.6.130 (unaffected)
Vendor states this is fixed in 7.0 (unaffected)

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-125

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