CVE-2026-74696 is a vulnerability in Linux Kernel
Published on August 22, 2026
tcp: fix TFO max_qlen accounting across reuseport migration
In the Linux kernel, the following vulnerability has been resolved:
tcp: fix TFO max_qlen accounting across reuseport migration
A listener's TCP_FASTOPEN max_qlen stops being accurate and lets through
far more pending Fast Open requests than it was configured for.
This only shows up with SO_REUSEPORT listener migration, where closing a
listener hands its still-pending TFO children over to a surviving one.
fastopenq.qlen is charged in tcp_fastopen_create_child() when the child
is created and uncharged in reqsk_fastopen_remove() when the handshake
completes. The uncharge follows rsk_listener of the request the child
points at, and inet_reqsk_clone() has repointed the child at a new
request owned by the new listener, so the ++ and the -- land on two
different sockets. The new listener's qlen drifts negative and its
limit no longer binds.
Charge the new listener during migration, like reqsk_queue_migrated()
already does for queue->young and queue->qlen.
Products Associated with CVE-2026-74696
Want to know whenever a new CVE is published for Linux Kernel? stack.watch will email you.
Affected Versions
Linux:- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below e98f0d80b9cccb5f828425d2004f9686e7d1ae24 is affected.
- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below b6247e0f96bd825ffb2005257f6177b5e642dee6 is affected.
- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below 585fc5247d14939a561056aa2addd9b7c2b1f670 is affected.
- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below 6e10ee56524a26b250229ad348637825646ddb88 is affected.
- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below a66e869cf0c90c1e47ae75f72b6482acbfc808ff is affected.
- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below d974618b2097453778389d385e3741629c40e0a3 is affected.
- Version 54b92e84193749c9968aff2dd46e3b0f42643e18 and below a0ab2ba83e35159d81cec830a92e885ecf8139be is affected.
- Version 5.14 is affected.
- Before 5.14 is unaffected.
- Version 5.15.216, <= 5.15.* is unaffected.
- Version 6.1.183, <= 6.1.* is unaffected.
- Version 6.6.152, <= 6.6.* is unaffected.
- Version 6.12.104, <= 6.12.* is unaffected.
- Version 6.18.45, <= 6.18.* is unaffected.
- Version 7.1.9, <= 7.1.* is unaffected.
- Version 7.2, <= * is unaffected.