CVE-2026-74704

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.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0c4882bff34558d8d53fb04c3e96da5c327c7dc8
https://git.kernel.org/stable/c/2504a76e5c0694e14e15562730e1339f2d9f9458
https://git.kernel.org/stable/c/2a33516f9ef59ad11844d4fc152f889449b5daf3
https://git.kernel.org/stable/c/a1ae353d8355407c1bea971d1c1af5e7f242bb7d
https://git.kernel.org/stable/c/a4b52612004a5639c4bfc30ba93ba414b8326e2a
https://git.kernel.org/stable/c/ae1b2f8e21a41e7c7e75511bea0c4ccc59ec1bd3
https://git.kernel.org/stable/c/c1693b7844a6c06d31a565e5a494948034dfd235
https://git.kernel.org/stable/c/cd2f1d9fe8a507c2dc86ad326fe221f121c47734

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-22 16:16

Updated : 2026-08-25 06:18

NVD link : CVE-2026-74704

Mitre link : CVE-2026-74704

CVE.ORG link : CVE-2026-74704

JSON object : View

Products Affected

No product.

CWE

No CWE.

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The parsing code contains a\nWARN_ON(1) which can be triggered by a malformed IP header in certain\ncases. Depending on the system configuration, this leads either to\neither spamming dmesg with warnings, or a panic if panic_on_warn is set.\n\nThe code already correctly skips the offending packet in the branch that\ntriggers the warning, so the WARN_ON itself doesn't really serve any\npurpose. So just drop it altogether to avoid the inconvenient side\neffects."}], "lastModified": "2026-08-25T06:18:54.583", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}