In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_conntrack_helper: pass helper to expect cleanup
nf_conntrack_helper_unregister() calls nf_ct_expect_iterate_destroy()
to remove expectations belonging to the helper being unregistered.
However, it passes NULL instead of the helper pointer as the data
argument, so expect_iter_me() never matches any expectation and all
of them survive the cleanup.
After unregister returns, nfnl_cthelper_del() frees the helper
object immediately. Subsequent expectation dumps or packet-driven
init_conntrack() calls then dereference the freed exp->helper,
causing a use-after-free.
Pass the actual helper pointer so expectations referencing it are
properly destroyed before the helper object is freed.
BUG: KASAN: slab-use-after-free in string+0x38f/0x430
Read of size 1 at addr ffff888003b14d20 by task poc/103
Call Trace:
string+0x38f/0x430
vsnprintf+0x3cc/0x1170
seq_printf+0x17a/0x240
exp_seq_show+0x2e5/0x560
seq_read_iter+0x419/0x1280
proc_reg_read+0x1ac/0x270
vfs_read+0x179/0x930
ksys_read+0xef/0x1c0
Freed by task 103:
The buggy address is located 32 bytes inside of
freed 192-byte region [ffff888003b14d00, ffff888003b14dc0)
References
Configurations
Configuration 1 (hide)
|
History
08 May 2026, 18:29
| Type | Values Removed | Values Added |
|---|---|---|
| CPE | cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* |
|
| References | () https://git.kernel.org/stable/c/2c16e4d64dd91227742dfe196a3e7b0568bef65a - Patch | |
| References | () https://git.kernel.org/stable/c/2cf2737c85a2ba2b52024dafe68ffad2676f97be - Patch | |
| References | () https://git.kernel.org/stable/c/504ba4168466c91210c45acdc332479cfd5f2da6 - Patch | |
| References | () https://git.kernel.org/stable/c/5cf28d5c8dcbbe8af6d3b145babe491906d7bad1 - Patch | |
| References | () https://git.kernel.org/stable/c/620f3d14c1ef51d425060a3056ad8dbae8f998a3 - Patch | |
| References | () https://git.kernel.org/stable/c/90bd7e8501349db3006d21fbc09df9ffcb172965 - Patch | |
| References | () https://git.kernel.org/stable/c/a242a9ae58aa46ff7dae51ce64150a93957abe65 - Patch | |
| References | () https://git.kernel.org/stable/c/dc1739eff48e34cc71d4e2f03715493fbcebd8af - Patch | |
| First Time |
Linux linux Kernel
Linux |
|
| CWE | CWE-416 | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 7.8 |
01 May 2026, 15:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-05-01 15:16
Updated : 2026-05-08 18:29
NVD link : CVE-2026-43027
Mitre link : CVE-2026-43027
CVE.ORG link : CVE-2026-43027
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
Use After Free