What is the CVSS score of CVE-2025-39673?

CVE-2025-39673 has a CVSS 3.1 base score of 4.7 (Medium). CVSS vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.0%.

Which versions of Linux are affected by CVE-2025-39673?

CVE-2025-39673 presents moderate security risk, a race condition vulnerability rated CVSS 4.7. Exploitation could compromise the security of affected deployments.. A patch is available.

How to fix or mitigate CVE-2025-39673?

During next maintenance window: Identify affected systems and apply vendor patches when convenient. Vendor patch is available.

Linux CVE-2025-39673

MEDIUM

Race Condition (CWE-362)

2025-09-05 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Information Disclosure Linux Race Condition

4.7

CVSS 3.1

CVSS VectorNVD

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

Attack Vector

Local

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:10 vuln.today

Patch released

Mar 28, 2026 - 19:10 nvd

Patch available

CVE Published

Sep 05, 2025 - 18:15 nvd

MEDIUM 4.7

DescriptionNVD

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

ppp: fix race conditions in ppp_fill_forward_path

ppp_fill_forward_path() has two race conditions:

The ppp->channels list can change between list_empty() and

list_first_entry(), as ppp_lock() is not held. If the only channel is deleted in ppp_disconnect_channel(), list_first_entry() may access an empty head or a freed entry, and trigger a panic.

pch->chan can be NULL. When ppp_unregister_channel() is called,

pch->chan is set to NULL before pch is removed from ppp->channels.

Fix these by using a lockless RCU approach:

Use list_first_or_null_rcu() to safely test and access the first list

entry.

Convert list modifications on ppp->channels to their RCU variants and

add synchronize_net() after removal.

Check for a NULL pch->chan before dereferencing it.

AnalysisAI

In the Linux kernel, the following vulnerability has been resolved: ppp: fix race conditions in ppp_fill_forward_path ppp_fill_forward_path() has two race conditions: 1. Rated medium severity (CVSS 4.7).

Technical ContextAI

This vulnerability is classified under CWE-362. In the Linux kernel, the following vulnerability has been resolved: ppp: fix race conditions in ppp_fill_forward_path ppp_fill_forward_path() has two race conditions: 1. The ppp->channels list can change between list_empty() and list_first_entry(), as ppp_lock() is not held. If the only channel is deleted in ppp_disconnect_channel(), list_first_entry() may access an empty head or a freed entry, and trigger a panic. 2. pch->chan can be NULL. When ppp_unregister_channel() is called, pch->chan is set to NULL before pch is removed from ppp->channels. Fix these by using a lockless RCU approach: - Use list_first_or_null_rcu() to safely test and access the first list entry. - Convert list modifications on ppp->channels to their RCU variants and add synchronize_net() after removal. - Check for a NULL pch->chan before dereferencing it. Affected products include: Linux Linux Kernel, Debian Debian Linux.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.