CVE-2025-38552

Medium

Elevated severity or exploit probability.

CVSS base

9.4 CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

EPSS — probability of exploitation (30 days)

0.3%

24.4th percentile

CISA KEV

Not listed

Weakness / dates

—

Published 2025-08-16 · modified 2026-07-30

CVSS breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	L	Low
Integrity	H	High
Availability	H	High

Timeline

2025-08-16 — Published (NVD)
2026-07-30 — Last modified (NVD)

Description

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

Affected

debian linux

References

Official: NVD · CVE.org