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

184 affected componentsFixes available
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
debian/linux
6.1.176-16.1.190-16.12.107-16.12.113-17.2.12-17.2.13-1
ubuntu/linux-hwe-edge*
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-azure*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gke-4.15*
ubuntu/linux-gke-5.4*
ubuntu/linux-gkeop-5.4*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-5.11*
ubuntu/linux-aws-5.13*
ubuntu/linux-aws-5.15*
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.11*
ubuntu/linux-azure-5.13*
ubuntu/linux-azure-5.15*
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.15*
ubuntu/linux-gcp-5.11*
ubuntu/linux-gcp-5.13*
ubuntu/linux-gcp-5.15*
ubuntu/linux-gcp-5.8*
ubuntu/linux-gke*
ubuntu/linux-gke-5.15*
ubuntu/linux-gkeop*
ubuntu/linux-gkeop-5.15*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.13*
ubuntu/linux-hwe-5.15*
ubuntu/linux-hwe-5.8*
ubuntu/linux-ibm-5.15*
ubuntu/linux-intel-5.13*
ubuntu/linux-intel-iotg-5.15*
ubuntu/linux-lowlatency-hwe-5.15*
ubuntu/linux-nvidia-tegra-5.15*
ubuntu/linux-oem-5.10*
ubuntu/linux-oem-5.13*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.11*
ubuntu/linux-oracle-5.13*
ubuntu/linux-oracle-5.15*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.11*
ubuntu/linux-riscv-5.15*
ubuntu/linux-riscv-5.8*
ubuntu/linux*
ubuntu/linux-allwinner-5.19*
ubuntu/linux-aws*
ubuntu/linux-aws-5.19*
ubuntu/linux-aws-6.2*
ubuntu/linux-aws-6.5*
ubuntu/linux-aws-6.8<6.8.0-1046.49~22.04.1
6.8.0-1046.49~22.04.1
ubuntu/linux-azure*
ubuntu/linux-azure-5.19*
ubuntu/linux-azure-6.2*
ubuntu/linux-azure-6.5*
ubuntu/linux-azure-6.8<6.8.0-1051.57~22.04.1
6.8.0-1051.57~22.04.1
ubuntu/linux-azure-fde*
ubuntu/linux-azure-fde-5.19*
ubuntu/linux-azure-fde-6.2*
ubuntu/linux-azure-fde-6.8<6.8.0-1046.53~22.04.1
6.8.0-1046.53~22.04.1
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.19*
ubuntu/linux-gcp-6.2*
ubuntu/linux-gcp-6.5*
ubuntu/linux-gcp-6.8<6.8.0-1047.50~22.04.2
6.8.0-1047.50~22.04.2
ubuntu/linux-gke*
ubuntu/linux-gkeop*
ubuntu/linux-hwe-5.19*
ubuntu/linux-hwe-6.2*
ubuntu/linux-hwe-6.5*
ubuntu/linux-hwe-6.8<6.8.0-100.100~22.04.1
6.8.0-100.100~22.04.1
ubuntu/linux-ibm*
ubuntu/linux-ibm-6.8<6.8.0-1044.44~22.04.1
6.8.0-1044.44~22.04.1
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-intel-iotg*
ubuntu/linux-kvm*
ubuntu/linux-lowlatency*
ubuntu/linux-lowlatency-hwe-5.19*
ubuntu/linux-lowlatency-hwe-6.2*
ubuntu/linux-lowlatency-hwe-6.5*
ubuntu/linux-lowlatency-hwe-6.8<6.8.0-100.100.1~22.04.1
6.8.0-100.100.1~22.04.1
ubuntu/linux-nvidia*
ubuntu/linux-nvidia-6.2*
ubuntu/linux-nvidia-6.5*
ubuntu/linux-nvidia-6.8<6.8.0-1046.49~22.04.1
6.8.0-1046.49~22.04.1
ubuntu/linux-nvidia-tegra*
ubuntu/linux-nvidia-tegra-igx*
ubuntu/linux-oem-5.17*
ubuntu/linux-oem-6.0*
ubuntu/linux-oem-6.1*
ubuntu/linux-oem-6.5*
ubuntu/linux-oracle*
ubuntu/linux-oracle-6.5*
ubuntu/linux-oracle-6.8<6.8.0-1043.44~22.04.1
6.8.0-1043.44~22.04.1
ubuntu/linux-raspi*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.19*
ubuntu/linux-riscv-6.5*
ubuntu/linux-riscv-6.8<6.8.0-100.100~22.04.1
6.8.0-100.100~22.04.1
ubuntu/linux-starfive-5.19*
ubuntu/linux-starfive-6.2*
ubuntu/linux-starfive-6.5*
ubuntu/linux-xilinx-zynqmp*
ubuntu/linux-bluefield*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-realtime-6.8<6.8.1-1041.42~22.04.1
6.8.1-1041.42~22.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<6.8.0-100.100
6.8.0-100.100
ubuntu/linux-aws<6.8.0-1046.49
6.8.0-1046.49
ubuntu/linux-aws-6.14<6.14.0-1017.17~24.04.1
6.14.0-1017.17~24.04.1
ubuntu/linux-azure<6.8.0-1046.52
6.8.0-1046.52
ubuntu/linux-azure-6.11*
ubuntu/linux-azure-6.14<6.14.0-1017.17~24.04.1
6.14.0-1017.17~24.04.1
ubuntu/linux-azure-fde<6.8.0-1046.53
6.8.0-1046.53
ubuntu/linux-azure-fde-6.14*
ubuntu/linux-azure-nvidia*
ubuntu/linux-azure-nvidia-6.14*
ubuntu/linux-gcp<6.8.0-1047.50
6.8.0-1047.50
ubuntu/linux-gcp-6.11*
ubuntu/linux-gcp-6.14<6.14.0-1020.21~24.04.1
6.14.0-1020.21~24.04.1
ubuntu/linux-gke<6.8.0-1043.48
6.8.0-1043.48
ubuntu/linux-gkeop<6.8.0-1030.33
6.8.0-1030.33
ubuntu/linux-hwe-6.11*
ubuntu/linux-ibm<6.8.0-1044.44
6.8.0-1044.44
ubuntu/linux-intel*
ubuntu/linux-lowlatency<6.8.0-100.100.1
6.8.0-100.100.1
ubuntu/linux-lowlatency-hwe-6.11*
ubuntu/linux-nvidia<6.8.0-1046.49
6.8.0-1046.49
ubuntu/linux-nvidia-6.11*
ubuntu/linux-nvidia-lowlatency<6.8.0-1046.49.1
6.8.0-1046.49.1
ubuntu/linux-nvidia-tegra<6.8.0-1020.20
6.8.0-1020.20
ubuntu/linux-oem-6.11*
ubuntu/linux-oem-6.14<6.14.0-1016.16
6.14.0-1016.16
ubuntu/linux-oem-6.8*
ubuntu/linux-oracle<6.8.0-1043.44
6.8.0-1043.44
ubuntu/linux-oracle-6.14<6.14.0-1017.17~24.04.1
6.14.0-1017.17~24.04.1
ubuntu/linux-raspi<6.8.0-1047.51
6.8.0-1047.51
ubuntu/linux-raspi-realtime*
ubuntu/linux-realtime*
ubuntu/linux-riscv*
ubuntu/linux-riscv-6.14<6.14.0-36.36.1~24.04.1
6.14.0-36.36.1~24.04.1
ubuntu/linux-xilinx<6.8.0-1023.24
6.8.0-1023.24
ubuntu/linux-bluefield<6.8.0-1016.20
6.8.0-1016.20
ubuntu/linux-raspi-realtime<6.8.0-2037.38
6.8.0-2037.38
ubuntu/linux-realtime<6.8.1-1041.42
6.8.1-1041.42
ubuntu/linux-realtime-6.14<6.14.0-1016.16~24.04.1
6.14.0-1016.16~24.04.1
ubuntu/linux-aws-fips<6.8.0-1046.49+fips1
6.8.0-1046.49+fips1
ubuntu/linux-azure-fips<6.8.0-1046.52+fips1
6.8.0-1046.52+fips1
ubuntu/linux-fips<6.8.0-100.100+fips1
6.8.0-100.100+fips1
ubuntu/linux-gcp-fips<6.8.0-1047.50+fips1
6.8.0-1047.50+fips1
ubuntu/linux-azure-fde*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/linux to a version that resolves this vulnerability.

    Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.113-1Fixed in 7.2.12-1Fixed in 7.2.13-1
  2. Upgrade

    Upgrade ubuntu/linux-aws-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.49~22.04.1
  3. Upgrade

    Upgrade ubuntu/linux-azure-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1051.57~22.04.1
  4. Upgrade

    Upgrade ubuntu/linux-azure-fde-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.53~22.04.1
  5. Upgrade

    Upgrade ubuntu/linux-gcp-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1047.50~22.04.2
  6. Upgrade

    Upgrade ubuntu/linux-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-100.100~22.04.1
  7. Upgrade

    Upgrade ubuntu/linux-ibm-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1044.44~22.04.1
  8. Upgrade

    Upgrade ubuntu/linux-lowlatency-hwe-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-100.100.1~22.04.1
  9. Upgrade

    Upgrade ubuntu/linux-nvidia-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.49~22.04.1
  10. Upgrade

    Upgrade ubuntu/linux-oracle-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-1043.44~22.04.1
  11. Upgrade

    Upgrade ubuntu/linux-riscv-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.0-100.100~22.04.1
  12. Upgrade

    Upgrade ubuntu/linux-realtime-6.8 to a version that resolves this vulnerability.

    Fixed in 6.8.1-1041.42~22.04.1
  13. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 6.8.0-100.100
  14. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.49
  15. Upgrade

    Upgrade ubuntu/linux-aws-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1017.17~24.04.1
  16. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.52
  17. Upgrade

    Upgrade ubuntu/linux-azure-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1017.17~24.04.1
  18. Upgrade

    Upgrade ubuntu/linux-azure-fde to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.53
  19. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 6.8.0-1047.50
  20. Upgrade

    Upgrade ubuntu/linux-gcp-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1020.21~24.04.1
  21. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 6.8.0-1043.48
  22. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 6.8.0-1030.33
  23. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 6.8.0-1044.44
  24. Upgrade

    Upgrade ubuntu/linux-lowlatency to a version that resolves this vulnerability.

    Fixed in 6.8.0-100.100.1
  25. Upgrade

    Upgrade ubuntu/linux-nvidia to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.49
  26. Upgrade

    Upgrade ubuntu/linux-nvidia-lowlatency to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.49.1
  27. Upgrade

    Upgrade ubuntu/linux-nvidia-tegra to a version that resolves this vulnerability.

    Fixed in 6.8.0-1020.20
  28. Upgrade

    Upgrade ubuntu/linux-oem-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1016.16
  29. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 6.8.0-1043.44
  30. Upgrade

    Upgrade ubuntu/linux-oracle-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1017.17~24.04.1
  31. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 6.8.0-1047.51
  32. Upgrade

    Upgrade ubuntu/linux-riscv-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-36.36.1~24.04.1
  33. Upgrade

    Upgrade ubuntu/linux-xilinx to a version that resolves this vulnerability.

    Fixed in 6.8.0-1023.24
  34. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 6.8.0-1016.20
  35. Upgrade

    Upgrade ubuntu/linux-raspi-realtime to a version that resolves this vulnerability.

    Fixed in 6.8.0-2037.38
  36. Upgrade

    Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.

    Fixed in 6.8.1-1041.42
  37. Upgrade

    Upgrade ubuntu/linux-realtime-6.14 to a version that resolves this vulnerability.

    Fixed in 6.14.0-1016.16~24.04.1
  38. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.49+fips1
  39. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1046.52+fips1
  40. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-100.100+fips1
  41. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 6.8.0-1047.50+fips1

Event History

Aug 16, 2025
CVE Published
via MITRE·11:34 AM
Data Sourced
via MITRE·11:34 AM
DescriptionSeverity
Data Sourced
via OSV·12:15 PM
DescriptionSeverityAffected Software
Event
via OSV·12:15 PM
Data Sourced
via NVD·12:15 PM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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.

Company

Resources

Contact

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