CVE-2026-74704
net/sched: sch_cake: drop WARN_ON(1) for malformed packets in ACK filter
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_cake: drop WARN_ON(1) for malformed packets in ACK filter The sch_cake ACK filter parses packets to find the TCP header and filter duplicated ACKs if the flow is backlogged. The parsing code contains a WARN_ON(1) which can be triggered by a malformed IP header in certain cases. Depending on the system configuration, this leads either to either spamming dmesg with warnings, or a panic if panic_on_warn is set. The code already correctly skips the offending packet in the branch that triggers the warning, so the WARN_ON itself doesn't really serve any purpose. So just drop it altogether to avoid the inconvenient side effects.
INFO
Published Date :
Aug. 22, 2026, 4:16 p.m.
Last Modified :
Aug. 22, 2026, 4:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Update the Linux kernel to the version where this fix is applied.
- Ensure the system is running a patched kernel version.
- Monitor system logs for unexpected warnings or panics.
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-2026-74704.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74704 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-2026-74704
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-2026-74704 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74704 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.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 22, 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': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': 'c1693b7844a6c06d31a565e5a494948034dfd235', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': 'a4b52612004a5639c4bfc30ba93ba414b8326e2a', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': 'ae1b2f8e21a41e7c7e75511bea0c4ccc59ec1bd3', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': '0c4882bff34558d8d53fb04c3e96da5c327c7dc8', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': '2504a76e5c0694e14e15562730e1339f2d9f9458', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': 'cd2f1d9fe8a507c2dc86ad326fe221f121c47734', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': 'a1ae353d8355407c1bea971d1c1af5e7f242bb7d', 'versionType': 'git'}, {'status': 'affected', 'version': '8b7138814f29933898ecd31dfc83e35a30ee69f5', 'lessThan': '2a33516f9ef59ad11844d4fc152f889449b5daf3', 'versionType': 'git'}], 'programFiles': ['net/sched/sch_cake.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.19'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.19', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.265', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.216', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.183', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.152', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.104', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.45', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.9', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/sch_cake.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_cake: drop WARN_ON(1) for malformed packets in ACK filter The sch_cake ACK filter parses packets to find the TCP header and filter duplicated ACKs if the flow is backlogged. The parsing code contains a WARN_ON(1) which can be triggered by a malformed IP header in certain cases. Depending on the system configuration, this leads either to either spamming dmesg with warnings, or a panic if panic_on_warn is set. The code already correctly skips the offending packet in the branch that triggers the warning, so the WARN_ON itself doesn't really serve any purpose. So just drop it altogether to avoid the inconvenient side effects. Added Reference https://git.kernel.org/stable/c/0c4882bff34558d8d53fb04c3e96da5c327c7dc8 Added Reference https://git.kernel.org/stable/c/2504a76e5c0694e14e15562730e1339f2d9f9458 Added Reference https://git.kernel.org/stable/c/2a33516f9ef59ad11844d4fc152f889449b5daf3 Added Reference https://git.kernel.org/stable/c/a1ae353d8355407c1bea971d1c1af5e7f242bb7d Added Reference https://git.kernel.org/stable/c/a4b52612004a5639c4bfc30ba93ba414b8326e2a Added Reference https://git.kernel.org/stable/c/ae1b2f8e21a41e7c7e75511bea0c4ccc59ec1bd3 Added Reference https://git.kernel.org/stable/c/c1693b7844a6c06d31a565e5a494948034dfd235 Added Reference https://git.kernel.org/stable/c/cd2f1d9fe8a507c2dc86ad326fe221f121c47734