CVE-2025-68221
Description
A logic error was found in the MPTCP (Multipath TCP) path manager in the Linux kernel. An inverted WARN_ON_ONCE condition in mptcp_pm_nl_rm_addr() causes address removal counter updates to only execute in the abnormal case (counter = 0) while normal removals are ignored. This breaks MPTCP address management.
Statement
MPTCP must be enabled and in active use for this to matter. The bug causes functional issues with multipath address management rather than memory corruption or crashes.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Other
Technical Impact: Alter Execution Logic
This weakness can cause unintended logic to be executed and other unexpected application behavior.
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