Linux Kernel up to 6.17.2 ipv4 dst_dev_rcu use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.17.2. This issue affects the function dst_dev_rcu of the component ipv4. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2025-40074. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.17.2. This issue affects the function dst_dev_rcu of the component ipv4. 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: ipv4: start using dst_dev_rcu() Change icmpv4_xrlim_allow(), ip_defrag() to prevent possible UAF. Change ipmr_prepare_xmit(), ipmr_queue_fwd_xmit(), ip_mr_output(), ipv4_neigh_lookup() to use lockdep enabled dst_dev_rcu().

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2025-40074 since 04/16/2025. 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 02/15/2026).

The vulnerability scanner Nessus provides a plugin with the ID 271868 (Linux Distros Unpatched Vulnerability : CVE-2025-40074), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.17.3 or 6.18-rc1 eliminates this vulnerability. Applying the patch 923e0734c386984d45de508528a7a7ad91d791cc/6ad8de3cefdb6ffa6708b21c567df0dbf82c43a8 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 (271868) and CERT Bund (WID-SEC-2025-2431). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • Microsoft Azure
  • 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: 8.0
VulDB Meta Temp Score: 7.6

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

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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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: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 271868
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-40074

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.17.3/6.18-rc1
Patch: 923e0734c386984d45de508528a7a7ad91d791cc/6ad8de3cefdb6ffa6708b21c567df0dbf82c43a8

Timelineinfo

04/16/2025 CVE reserved
10/28/2025 +195 days Advisory disclosed
10/28/2025 +0 days VulDB entry created
02/15/2026 +110 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-40074 (🔒)
GCVE (CVE): GCVE-0-2025-40074
GCVE (VulDB): GCVE-100-330257
CERT Bund: WID-SEC-2025-2431 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/28/2025 14:45
Updated: 02/15/2026 21:49
Changes: 10/28/2025 14:45 (59), 10/30/2025 07:49 (7), 10/30/2025 16:37 (2), 11/24/2025 23:11 (1), 12/22/2025 02:00 (1), 02/08/2026 18:13 (1), 02/15/2026 21:49 (1)
Complete: 🔍
Cache ID: 216::103

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

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