Linux Kernel up to 7.0-rc4 netfilter privilege escalation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 7.0-rc4. Impacted is an unknown function of the component netfilter. The manipulation leads to an unknown weakness. This vulnerability is referenced as CVE-2026-23391. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.0-rc4. It has been rated as critical. This issue affects an unknown code of the component netfilter. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_CT: drop pending enqueued packets on template removal Templates refer to objects that can go away while packets are sitting in nfqueue refer to: - helper, this can be an issue on module removal. - timeout policy, nfnetlink_cttimeout might remove it. The use of templates with zone and event cache filter are safe, since this just copies values. Flush these enqueued packets in case the template rule gets removed.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-23391 since 01/13/2026. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/16/2026).

The vulnerability scanner Nessus provides a plugin with the ID 303612 (Linux Distros Unpatched Vulnerability : CVE-2026-23391), 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 d2d0bae0c9a2a17b6990a2966f5cdce0813d6256/63b8097cea1923fe82cd598068d0796da8c015ec/19a230dec6bb8928e3f96387f9085cf2c79bcef9/cb549925875fa06dd155e49db4ac2c5044c30f9c/777d02efe3d630cca4c1b63962cec17c57711325/f62a218a946b19bb59abdd5361da85fa4606b96b 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 (303612) and CERT Bund (WID-SEC-2026-0861). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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: 6.6
VulDB Meta Temp Score: 6.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
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: Privilege escalation
CWE: Unknown
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: 303612
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-23391

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: d2d0bae0c9a2a17b6990a2966f5cdce0813d6256/63b8097cea1923fe82cd598068d0796da8c015ec/19a230dec6bb8928e3f96387f9085cf2c79bcef9/cb549925875fa06dd155e49db4ac2c5044c30f9c/777d02efe3d630cca4c1b63962cec17c57711325/f62a218a946b19bb59abdd5361da85fa4606b96b

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-2026-23391 (🔒)
GCVE (CVE): GCVE-0-2026-23391
GCVE (VulDB): GCVE-100-353105
CERT Bund: WID-SEC-2026-0861 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 03/25/2026 13:42
Updated: 07/16/2026 17:59
Changes: 03/25/2026 13:42 (57), 03/26/2026 00:43 (2), 03/30/2026 22:33 (1), 06/20/2026 16:51 (7), 07/16/2026 17:59 (11)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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