CVE-2026-97568

mptcp: syncookies: remember the request backup flag

State: Published
Severity: Not scored
Published: Sep 25, 2026
Updated: Oct 19, 2026
Reserved: Sep 24, 2026

Description

In the Linux kernel, the following vulnerability has been resolved:

mptcp: syncookies: remember the request backup flag

Instead of using an uninitialised bit when copying the info in subflow_ulp_clone().

To fix this, no need to extend the join_entry structure: backup is coming from struct mptcp_subflow_request_sock, only one bit. Do the same here by using one bit for both.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	1008f2bcbc8e461c1df3aebba30ac4f616ebe570 to before c97fa2c7ada82d4cac1c6c00643238dc4c462f15Affected 6f01f41b6a492ddf2da7609967cfaf57e7ca48a7 to before 1668b34452009d27be3262646de748a3e48ffd51Affected 09176f80995105c62939728fbad5c437d61e7ff4 to before b138e7dc719f0a3949de8bb6500b8cf1604eea06Affected 8ed3e34c766e8264d5d2e0436f86c51604d6a8a7 to before 360d99258a6402cb8e49771460944f19f04d25b7Affected efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before 61178d0b85b4b1b53e78b06e89d018d22d102f88Affected efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before 00b2bd518911e0daab00f4749cce68c191ccebb4Affected efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before 06d649f9cd03a9f8e768a658b20acf8d2c8022e0Affected efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before b76c0e28b392620dfbaf92cdeedbf115820b44cbAffected 73e2baa301ee3f62ff971e68877adeb37f98cc67Affected 5.10.224 to before 5.10.271Affected 5.15.165 to before 5.15.222Affected 6.1.104 to before 6.1.189Affected 6.6.45 to before 6.6.158Affected 6.10.4 to before 6.11Affected
LinuxLinux	6.11Affected before 6.11Not affected 5.10.271 through 5.10.Not affected 5.15.222 through 5.15.Not affected 6.1.189 through 6.1.Not affected 6.6.158 through 6.6.Not affected 6.12.111 through 6.12.Not affected 6.18.53 through 6.18.Not affected 7.2.7 through 7.2.*Not affected 7.3 and laterNot affected

Product

Versions

LinuxLinux

1008f2bcbc8e461c1df3aebba30ac4f616ebe570 to before c97fa2c7ada82d4cac1c6c00643238dc4c462f15Affected
6f01f41b6a492ddf2da7609967cfaf57e7ca48a7 to before 1668b34452009d27be3262646de748a3e48ffd51Affected
09176f80995105c62939728fbad5c437d61e7ff4 to before b138e7dc719f0a3949de8bb6500b8cf1604eea06Affected
8ed3e34c766e8264d5d2e0436f86c51604d6a8a7 to before 360d99258a6402cb8e49771460944f19f04d25b7Affected
efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before 61178d0b85b4b1b53e78b06e89d018d22d102f88Affected
efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before 00b2bd518911e0daab00f4749cce68c191ccebb4Affected
efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before 06d649f9cd03a9f8e768a658b20acf8d2c8022e0Affected
efd340bf3d7779a3a8ec954d8ec0fb8a10f24982 to before b76c0e28b392620dfbaf92cdeedbf115820b44cbAffected
73e2baa301ee3f62ff971e68877adeb37f98cc67Affected
5.10.224 to before 5.10.271Affected
5.15.165 to before 5.15.222Affected
6.1.104 to before 6.1.189Affected
6.6.45 to before 6.6.158Affected
6.10.4 to before 6.11Affected

LinuxLinux

6.11Affected
before 6.11Not affected
5.10.271 through 5.10.*Not affected
5.15.222 through 5.15.*Not affected
6.1.189 through 6.1.*Not affected
6.6.158 through 6.6.*Not affected
6.12.111 through 6.12.*Not affected
6.18.53 through 6.18.*Not affected
7.2.7 through 7.2.*Not affected
7.3 and laterNot affected

References

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