net/sched: sch_cake: drop WARN_ON(1) for malformed packets in ACK filter
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · None · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.265, 5.15.216, 6.1.183, 6.6.152, 6.12.104, 6.18.45, 7.1.9, 7.2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2026-74704
- 2026-10-03 Alias added: GHSA-5x69-69gj-gg3f
- 2026-10-18 CISA SSVC decision points changed
- 2026-10-18 Priority changed: LOW → MEDIUM
References
Other 8
- https://git.kernel.org/stable/c/c1693b7844a6c06d31a565e5a494948034dfd235
- https://git.kernel.org/stable/c/a4b52612004a5639c4bfc30ba93ba414b8326e2a
- https://git.kernel.org/stable/c/ae1b2f8e21a41e7c7e75511bea0c4ccc59ec1bd3
- https://git.kernel.org/stable/c/0c4882bff34558d8d53fb04c3e96da5c327c7dc8
- https://git.kernel.org/stable/c/2504a76e5c0694e14e15562730e1339f2d9f9458
- https://git.kernel.org/stable/c/cd2f1d9fe8a507c2dc86ad326fe221f121c47734
- https://git.kernel.org/stable/c/a1ae353d8355407c1bea971d1c1af5e7f242bb7d
- https://git.kernel.org/stable/c/2a33516f9ef59ad11844d4fc152f889449b5daf3
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- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
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- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-74704 · CVE Program
- CVE-2026-74704 · NVD
- FIRST EPSS
- GHSA-5x69-69gj-gg3f · GitHub Advisory Database · CC BY 4.0
- CVE-2026-74704 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences