Linux Kernel up to 6.6.18/6.7.6 tcf_mirred_forward use after free

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.6.18/6.7.6 and classified as problematic. This issue affects the function tcf_mirred_forward. The manipulation leads to use after free. This vulnerability is documented as CVE-2024-26739. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.18/6.7.6 and classified as problematic. This issue affects the function tcf_mirred_forward. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_mirred: don't override retval if we already lost the skb If we're redirecting the skb, and haven't called tcf_mirred_forward(), yet, we need to tell the core to drop the skb by setting the retcode to SHOT. If we have called tcf_mirred_forward(), however, the skb is out of our hands and returning SHOT will lead to UaF. Move the retval override to the error path which actually need it.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2024-26739 since 02/19/2024. 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 08/03/2025).

The vulnerability scanner Nessus provides a plugin with the ID 207776 (Oracle Linux 9 : kernel (ELSA-2024-6997)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.19, 6.7.7 or 6.8 eliminates this vulnerability. Applying the patch 28cdbbd38a44/f4e294bbdca8/166c2c8a6a4d 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 (207776) and CERT Bund (WID-SEC-2024-0773). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• NetApp FAS
• EMC Avamar
• Oracle VM
• NetApp AFF
• Dell NetWorker
• IBM Security Guardium
• RESF Rocky Linux
• Open Source Linux Kernel
• SolarWinds Security Event Manager
• Broadcom Brocade SANnav
• IBM Business Automation Workflow
• IBM Spectrum Protect Plus
• IBM QRadar SIEM
• Juniper Junos Space
• IBM DB2
• IBM Storage Scale System

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.7.0
• 6.7.1
• 6.7.2
• 6.7.3
• 6.7.4
• 6.7.5
• 6.7.6

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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

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