CVE-2026-74704High· 8.2▾ TwilightIn 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 th…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 45.1 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.4%
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.
Refer to the linked advisories for vendor-supplied fixes and affected version ranges.