netfilter: conntrack: Avoid nf_ct_helper_hash uses after free
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 4 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: Avoid nf_ct_helper_hash uses after free If nf_conntrack_init_start() fails (for example due to a register_nf_conntrack_bpf() failure), the nf_conntrack_helper_fini() clean-up path frees the nf_ct_helper_hash map. When built with NF_CONNTRACK=y, further netfilter modules (e.g: netfilter_conntrack_ftp) can still be loaded and call nf_conntrack_helpers_register(), independently of whether nf_conntrack initialized correctly. This accesses the nf_ct_helper_hash dangling pointer and causes a uaf, possibly leading to random memory corruption. This patch guards nf_conntrack_helper_register() from accessing a freed or uninitialized nf_ct_helper_hash pointer and fixes possible uses-after-free when loading a conntrack module.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 3.6 and later | 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.121, 6.1.39, 6.4.4, 6.5 | Patch available | CNA |
- Linux VendorLinux Affected 3.6 and later Fixed in 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.121, 6.1.39, 6.4.4, 6.5 Patch available CNA
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 3.6 to before 4.14.322; 4.15 to before 4.19.291; 4.20 to before 5.4.251; 5.5 to before 5.10.188; 5.11 to before 5.15.121; 5.16 to before 6.1.39; 6.2 to before 6.4.4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.5:rc1:*:*:*:*:*:* | 6.5 rc1 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 3.6 to before 4.14.322; 4.15 to before 4.19.291; 4.20 to before 5.4.251; 5.5 to before 5.10.188; 5.11 to before 5.15.121; 5.16 to before 6.1.39; 6.2 to before 6.4.4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.5:rc1:*:*:*:*:*:* Versions 6.5 rc1 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.121, 6.1.39, 6.4.4, 6.5
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Enterprise Linux 10
Timeline
- 2026-10-02 Threatist record created from CVE-2023-53619
- 2026-10-03 Alias added: GHSA-fj8x-7xh8-225g
- 2026-10-16 CISA SSVC decision points changed
References
Patch 8
- https://git.kernel.org/stable/c/4ee69c91cb8f9ca144bc0861969e5a1a3c6152a7
- https://git.kernel.org/stable/c/00716f25f9697d02a0d9bd622575c7c7321ba3d0
- https://git.kernel.org/stable/c/61c7a5256543ae7d24cd9d21853d514c8632e1e9
- https://git.kernel.org/stable/c/8289d422f5e484efe4a565fe18e862ecd621c175
- https://git.kernel.org/stable/c/6f03ce2f1abcb9f9d0511e3659ca6eb60e39f566
- https://git.kernel.org/stable/c/05561f822f27b9fa88fa5504ddec34bf38833034
- https://git.kernel.org/stable/c/fce5cc7cbd4b92f979bf02c9ec5fb69aaeba92d7
- https://git.kernel.org/stable/c/6eef7a2b933885a17679eb8ed0796ddf0ee5309b
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2023-53619 · CVE Program
- CVE-2023-53619 · NVD
- FIRST EPSS
- GHSA-fj8x-7xh8-225g · GitHub Advisory Database · CC BY 4.0
- CVE-2023-53619 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences