Linux Kernel up to 7.0-rc4 nf_tables synchronize_rcu use after free

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

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 7.0-rc4. The affected element is the function synchronize_rcu of the component nf_tables. The manipulation results in use after free. This vulnerability is identified as CVE-2026-23392. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 7.0-rc4. Affected is the function synchronize_rcu of the component nf_tables. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: release flowtable after rcu grace period on error Call synchronize_rcu() after unregistering the hooks from error path, since a hook that already refers to this flowtable can be already registered, exposing this flowtable to packet path and nfnetlink_hook control plane. This error path is rare, it should only happen by reaching the maximum number hooks or by failing to set up to hardware offload, just call synchronize_rcu(). There is a check for already used device hooks by different flowtable that could result in EEXIST at this late stage. The hook parser can be updated to perform this check earlier to this error path really becomes rarely exercised. Uncovered by KASAN reported as use-after-free from nfnetlink_hook path when dumping hooks.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-23392 since 01/13/2026. The exploitability is told to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/16/2026).

The vulnerability scanner Nessus provides a plugin with the ID 311783 (Debian dla-4561 : linux-config-6.1 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.167, 6.6.130, 6.12.78, 6.18.20, 6.19.10 or 7.0-rc5 eliminates this vulnerability. Applying the patch d2632de96ccb066e0131ad1494241b9c281c60b8/adee3436ccd29f1e514c028899e400cbc6d84065/7e3955b282eae20d61c75e499c75eade51c20060/c8092edb9a11f20f95ccceeb9422b7dd0df337bd/e78a2dcc7cfb87b64a631441ca7681492b347ef6/d73f4b53aaaea4c95f245e491aa5eeb8a21874ce 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 (311783) and CERT Bund (WID-SEC-2026-0861). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Google Cloud Platform
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux

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: 🔍

CNA Base Score: 7.8
CNA Vector (Linux): 🔒

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / 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: 311783
Nessus Name: Debian dla-4561 : linux-config-6.1 - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.167/6.6.130/6.12.78/6.18.20/6.19.10/7.0-rc5
Patch: d2632de96ccb066e0131ad1494241b9c281c60b8/adee3436ccd29f1e514c028899e400cbc6d84065/7e3955b282eae20d61c75e499c75eade51c20060/c8092edb9a11f20f95ccceeb9422b7dd0df337bd/e78a2dcc7cfb87b64a631441ca7681492b347ef6/d73f4b53aaaea4c95f245e491aa5eeb8a21874ce

Timelineinfo

01/13/2026 CVE reserved
03/25/2026 +71 days Advisory disclosed
03/25/2026 +0 days VulDB entry created
07/16/2026 +113 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23392 (🔒)
GCVE (CVE): GCVE-0-2026-23392
GCVE (VulDB): GCVE-100-353106
CERT Bund: WID-SEC-2026-0861 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 03/25/2026 13:43
Updated: 07/16/2026 17:59
Changes: 03/25/2026 13:43 (59), 03/30/2026 22:33 (1), 05/04/2026 06:12 (2), 06/20/2026 16:51 (7), 07/16/2026 17:59 (11)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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