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7.5
HIGH CVSS 3.1
CVE-2026-72254
netfilter: nft_fib: reject fib expression on the netdev egress hook
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_fib: reject fib expression on the netdev egress hook A fib expression in a netdev egress base chain dereferences nft_in(pkt), NULL on the transmit path, causing a NULL pointer dereference at eval. nft_fib_validate() masks the hook with NF_INET_* values, but netdev hook numbers are a separate enum that aliases them (NF_NETDEV_EGRESS == NF_INET_LOCAL_IN), so an egress chain passes validation and then faults. Add nft_fib_netdev_validate() that limits each result/flag to the netdev hook where the device it reads exists: the input-device cases (OIF, OIFNAME, ADDRTYPE with F_IIF) to ingress, the output-device case (ADDRTYPE with F_OIF) to egress, ADDRTYPE with no device flag to both. Also restrict nft_fib_validate() to NFPROTO_IPV4/IPV6/INET so its NF_INET_* masks are not applied to another family's hooks.

Details
INFO

Published Date :

Aug. 15, 2026, 6:21 a.m.

Last Modified :

Aug. 17, 2026, 6:18 a.m.

Remotely Exploit :

Yes !

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-72254 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Apply kernel updates to fix NULL pointer dereference on egress hook.
  • Update the Linux kernel to the latest version.
  • Verify the fix is applied to the netfilter module.
  • Test system stability on the egress path.
References
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-72254.

URL Resource
https://git.kernel.org/stable/c/4fee43759b489559a491f7c95f9bfa7a1d0c7a10
https://git.kernel.org/stable/c/568931f26af4727a51e8521f72efbc78d3b82410
https://git.kernel.org/stable/c/d01c913febead04a01a5f3a6374d1f45504dc523
https://git.kernel.org/stable/c/d07955dd34ecae17d35d8c7d0a273a3fba653a8c
https://git.kernel.org/stable/c/f68305267ebda7e839b5e8f77e8d77535a3d5a0f
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-72254 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-72254 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-72254 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-72254 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Aug. 17, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': '4fee43759b489559a491f7c95f9bfa7a1d0c7a10', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': '568931f26af4727a51e8521f72efbc78d3b82410', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'd01c913febead04a01a5f3a6374d1f45504dc523', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'f68305267ebda7e839b5e8f77e8d77535a3d5a0f', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'd07955dd34ecae17d35d8c7d0a273a3fba653a8c', 'versionType': 'git'}], 'programFiles': ['net/netfilter/nft_fib.c', 'net/netfilter/nft_fib_netdev.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.16'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.16', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/netfilter/nft_fib.c', 'net/netfilter/nft_fib_netdev.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': '4fee43759b489559a491f7c95f9bfa7a1d0c7a10', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': '568931f26af4727a51e8521f72efbc78d3b82410', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'd01c913febead04a01a5f3a6374d1f45504dc523', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'f68305267ebda7e839b5e8f77e8d77535a3d5a0f', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'd07955dd34ecae17d35d8c7d0a273a3fba653a8c', 'versionType': 'git'}], 'programFiles': ['net/netfilter/nft_fib.c', 'net/netfilter/nft_fib_netdev.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.16'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.16', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/netfilter/nft_fib.c', 'net/netfilter/nft_fib_netdev.c'], 'defaultStatus': 'affected'}]
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Aug. 15, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': '4fee43759b489559a491f7c95f9bfa7a1d0c7a10', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': '568931f26af4727a51e8521f72efbc78d3b82410', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'd01c913febead04a01a5f3a6374d1f45504dc523', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'f68305267ebda7e839b5e8f77e8d77535a3d5a0f', 'versionType': 'git'}, {'status': 'affected', 'version': '42df6e1d221dddc0f2acf2be37e68d553ad65f96', 'lessThan': 'd07955dd34ecae17d35d8c7d0a273a3fba653a8c', 'versionType': 'git'}], 'programFiles': ['net/netfilter/nft_fib.c', 'net/netfilter/nft_fib_netdev.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.16'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.16', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/netfilter/nft_fib.c', 'net/netfilter/nft_fib_netdev.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_fib: reject fib expression on the netdev egress hook A fib expression in a netdev egress base chain dereferences nft_in(pkt), NULL on the transmit path, causing a NULL pointer dereference at eval. nft_fib_validate() masks the hook with NF_INET_* values, but netdev hook numbers are a separate enum that aliases them (NF_NETDEV_EGRESS == NF_INET_LOCAL_IN), so an egress chain passes validation and then faults. Add nft_fib_netdev_validate() that limits each result/flag to the netdev hook where the device it reads exists: the input-device cases (OIF, OIFNAME, ADDRTYPE with F_IIF) to ingress, the output-device case (ADDRTYPE with F_OIF) to egress, ADDRTYPE with no device flag to both. Also restrict nft_fib_validate() to NFPROTO_IPV4/IPV6/INET so its NF_INET_* masks are not applied to another family's hooks.
    Added Reference https://git.kernel.org/stable/c/4fee43759b489559a491f7c95f9bfa7a1d0c7a10
    Added Reference https://git.kernel.org/stable/c/568931f26af4727a51e8521f72efbc78d3b82410
    Added Reference https://git.kernel.org/stable/c/d01c913febead04a01a5f3a6374d1f45504dc523
    Added Reference https://git.kernel.org/stable/c/d07955dd34ecae17d35d8c7d0a273a3fba653a8c
    Added Reference https://git.kernel.org/stable/c/f68305267ebda7e839b5e8f77e8d77535a3d5a0f
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.5
Attack Vector
Attack Complexity
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Scope
Confidentiality Impact
Integrity Impact
Availability Impact