Linux Kernel up to 6.4.3 nf_conntrack_init_start memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.4.3. This issue affects the function nf_conntrack_init_start. The manipulation leads to memory corruption. This vulnerability is referenced as CVE-2023-53619. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.4.3. This issue affects the function nf_conntrack_init_start. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2023-53619 since 10/07/2025. The exploitation is known to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/20/2026).

The vulnerability scanner Nessus provides a plugin with the ID 276910 (SUSE SLES12 Security Update : kernel (SUSE-SU-2025:4189-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.322, 4.19.291, 5.4.251, 5.10.188, 5.15.121, 6.1.39 or 6.4.4 eliminates this vulnerability. Applying the patch 4ee69c91cb8f9ca144bc0861969e5a1a3c6152a7/00716f25f9697d02a0d9bd622575c7c7321ba3d0/61c7a5256543ae7d24cd9d21853d514c8632e1e9/8289d422f5e484efe4a565fe18e862ecd621c175/6f03ce2f1abcb9f9d0511e3659ca6eb60e39f566/05561f822f27b9fa88fa5504ddec34bf38833034/fce5cc7cbd4b92f979bf02c9ec5fb69aaeba92d7/6eef7a2b933885a17679eb8ed0796ddf0ee5309b is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (276910) and CERT Bund (WID-SEC-2025-2229). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • IBM QRadar SIEM
  • Dell NetWorker

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 276910
Nessus Name: SUSE SLES12 Security Update : kernel (SUSE-SU-2025:4189-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.14.322/4.19.291/5.4.251/5.10.188/5.15.121/6.1.39/6.4.4
Patch: 4ee69c91cb8f9ca144bc0861969e5a1a3c6152a7/00716f25f9697d02a0d9bd622575c7c7321ba3d0/61c7a5256543ae7d24cd9d21853d514c8632e1e9/8289d422f5e484efe4a565fe18e862ecd621c175/6f03ce2f1abcb9f9d0511e3659ca6eb60e39f566/05561f822f27b9fa88fa5504ddec34bf38833034/fce5cc7cbd4b92f979bf02c9ec5fb69aaeba92d7/6eef7a2b933885a17679eb8ed0796ddf0ee5309b

Timelineinfo

10/07/2025 Advisory disclosed
10/07/2025 +0 days CVE reserved
10/07/2025 +0 days VulDB entry created
04/20/2026 +195 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53619 (🔒)
GCVE (CVE): GCVE-0-2023-53619
GCVE (VulDB): GCVE-100-327485
CERT Bund: WID-SEC-2025-2229 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/07/2025 19:26
Updated: 04/20/2026 03:09
Changes: 10/07/2025 19:26 (58), 11/23/2025 00:18 (7), 11/27/2025 21:08 (2), 12/22/2025 08:14 (1), 02/05/2026 19:47 (11), 03/01/2026 08:37 (1), 04/20/2026 03:09 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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