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8.2
HIGH CVSS 3.1
CVE-2026-72057
net/sched: act_ct: preserve tc_skb_cb across defragmentation
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: preserve tc_skb_cb across defragmentation tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through act_ct therefore loses qdisc metadata such as pkt_segs and can trigger WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled. Save and restore the full tc_skb_cb around nf_ct_handle_fragments(), matching the pattern used by ovs_ct_handle_fragments().

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-2026-72057 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
Preserve control buffer data across fragmentation by saving and restoring tc_skb_cb.
  • Save tc_skb_cb before handling fragments.
  • Restore tc_skb_cb after handling fragments.
  • Update the Linux kernel to the patched version.
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-2026-72057.

URL Resource
https://git.kernel.org/stable/c/2400c4b05d58834b994500a9eec90a37db44187c
https://git.kernel.org/stable/c/5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac
https://git.kernel.org/stable/c/9092e15defbe6c7bc241c306093ca9d358a578e7
https://git.kernel.org/stable/c/b3d835407846134b0d54637c0281b39bebef831d
https://git.kernel.org/stable/c/f7f45ceb855d9ba1cba594fb3f383255f7013fad
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-72057 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-2026-72057 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-2026-72057 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-2026-72057 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:L/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': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '2400c4b05d58834b994500a9eec90a37db44187c', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': 'b3d835407846134b0d54637c0281b39bebef831d', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': 'f7f45ceb855d9ba1cba594fb3f383255f7013fad', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '9092e15defbe6c7bc241c306093ca9d358a578e7', 'versionType': 'git'}, {'status': 'affected', 'version': '0d76daf2013ce1da20eab5e26bd81d983e1c18fb', 'versionType': 'git'}, {'status': 'affected', 'version': '5.15.13', 'lessThan': '5.16', 'versionType': 'semver'}], 'programFiles': ['net/sched/act_ct.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': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/act_ct.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '2400c4b05d58834b994500a9eec90a37db44187c', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': 'b3d835407846134b0d54637c0281b39bebef831d', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': 'f7f45ceb855d9ba1cba594fb3f383255f7013fad', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '9092e15defbe6c7bc241c306093ca9d358a578e7', 'versionType': 'git'}, {'status': 'affected', 'version': '0d76daf2013ce1da20eab5e26bd81d983e1c18fb', 'versionType': 'git'}, {'status': 'affected', 'version': '5.15.13', 'lessThan': '5.16', 'versionType': 'semver'}], 'programFiles': ['net/sched/act_ct.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': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', '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/sched/act_ct.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': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '2400c4b05d58834b994500a9eec90a37db44187c', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': 'b3d835407846134b0d54637c0281b39bebef831d', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': 'f7f45ceb855d9ba1cba594fb3f383255f7013fad', 'versionType': 'git'}, {'status': 'affected', 'version': 'ec624fe740b416fb68d536b37fb8eef46f90b5c2', 'lessThan': '9092e15defbe6c7bc241c306093ca9d358a578e7', 'versionType': 'git'}, {'status': 'affected', 'version': '0d76daf2013ce1da20eab5e26bd81d983e1c18fb', 'versionType': 'git'}, {'status': 'affected', 'version': '5.15.13', 'lessThan': '5.16', 'versionType': 'semver'}], 'programFiles': ['net/sched/act_ct.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': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/act_ct.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: net/sched: act_ct: preserve tc_skb_cb across defragmentation tcf_ct_handle_fragments() calls nf_ct_handle_fragments() without saving and restoring skb->cb. The defrag helper clears IPCB/IP6CB, which aliases the tc_skb_cb/qdisc_skb_cb control buffer. Fragmented traffic through act_ct therefore loses qdisc metadata such as pkt_segs and can trigger WARN_ON_ONCE() in qdisc_pkt_segs() when panic_on_warn is enabled. Save and restore the full tc_skb_cb around nf_ct_handle_fragments(), matching the pattern used by ovs_ct_handle_fragments().
    Added Reference https://git.kernel.org/stable/c/2400c4b05d58834b994500a9eec90a37db44187c
    Added Reference https://git.kernel.org/stable/c/5c3ae5f6c7c6de73ea9b6a75154fe4ed343e1bac
    Added Reference https://git.kernel.org/stable/c/9092e15defbe6c7bc241c306093ca9d358a578e7
    Added Reference https://git.kernel.org/stable/c/b3d835407846134b0d54637c0281b39bebef831d
    Added Reference https://git.kernel.org/stable/c/f7f45ceb855d9ba1cba594fb3f383255f7013fad
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: 8.2
Attack Vector
Attack Complexity
Privileges Required
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Scope
Confidentiality Impact
Integrity Impact
Availability Impact