CVE-2025-38552: mptcp: plug races between subflow fail and subflow creation

Published Aug 16, 2025
·
Updated

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

mptcp: plug races between subflow fail and subflow creation

We have races similar to the one addressed by the previous patch between subflow failing and additional subflow creation. They are just harder to trigger.

The solution is similar. Use a separate flag to track the condition 'socket state prevent any additional subflow creation' protected by the fallback lock.

The socket fallback makes such flag true, and also receiving or sending an MPFAIL option.

The field 'allowinfinitefallback' is now always touched under the relevant lock, we can drop the ONCE annotation on write.

Affected Software

12 affected components
Linux Linux kernel
Linux Linux kernel>=5.15<6.1.149
Linux Linux kernel>=6.2<6.6.101
Linux Linux kernel>=6.7<6.12.40
Linux Linux kernel>=6.13<6.15.8
Linux Linux kernel=6.16-rc1
Linux Linux kernel=6.16-rc2
Linux Linux kernel=6.16-rc3
Linux Linux kernel=6.16-rc4
Linux Linux kernel=6.16-rc5
Linux Linux kernel=6.16-rc6
Debian Debian Linux=11.0

Event History

Aug 16, 2025
CVE Published
via MITRE·11:34 AM
Data Sourced
via MITRE·11:34 AM
DescriptionSeverity
Data Sourced
via NVD·12:15 PM
RemedyDescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2025-38552?

CVE-2025-38552 has been classified with a severity level indicating potential impacts on system security and stability.

2

How do I fix CVE-2025-38552?

To address CVE-2025-38552, users should update to the latest stable version of the Linux kernel that includes the patch.

3

What impact does CVE-2025-38552 have on system performance?

CVE-2025-38552 may lead to performance degradation under certain race conditions in the mptcp functionality.

4

Is CVE-2025-38552 exploitable remotely?

CVE-2025-38552 may be exploitable remotely given its nature related to the mptcp protocol.

5

What versions of Linux Kernel are affected by CVE-2025-38552?

CVE-2025-38552 affects multiple versions of the Linux Kernel that use the mptcp capability.

Contact

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