CVE-2017-18224: Race Condition

Q: Who can exploit this issue?

An attacker needs local access and low-privileged access sufficient to modify the relevant e_cpos field. The CVSS vector indicates no user interaction is required.

Q: What is the likely impact of successful exploitation?

Successful exploitation can trigger a kernel BUG, resulting in a denial of service. The provided CVSS vector indicates availability impact only, with no stated confidentiality or integrity impact.

Q: Which systems are affected?

The issue affects Linux kernel versions before 4.15 in the OCFS2 filesystem code path, specifically during DIRECT-mode read operations involving extent-tree access.

Q: Is this easy to exploit remotely?

No. The vulnerability is locally exploitable, and the CVSS vector rates attack complexity as high; no network attack vector is indicated.

Published Mar 12, 2018

Updated

In the Linux kernel before 4.15, fs/ocfs2/aops.c omits use of a semaphore and consequently has a race condition for access to the extent tree during read operations in DIRECT mode, which allows local users to cause a denial of service (BUG) by modifying a certain ecpos field.

Affected Software

2 affected componentsFixes available

Linux Linux kernel<4.15

debian/linux

6.1.176-16.1.190-16.12.107-16.12.113-17.2.12-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

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 7.2.12-1

Event History

Mar 12, 2018

CVE Published

via MITRE·03:00 AM

Data Sourced

via MITRE·03:00 AM

Description

Parent advisories

This vulnerability appears in the following advisories.

DSA-4188

Frequently Asked Questions

Who can exploit this issue?

An attacker needs local access and low-privileged access sufficient to modify the relevant e_cpos field. The CVSS vector indicates no user interaction is required.

What is the likely impact of successful exploitation?

Successful exploitation can trigger a kernel BUG, resulting in a denial of service. The provided CVSS vector indicates availability impact only, with no stated confidentiality or integrity impact.

Which systems are affected?

The issue affects Linux kernel versions before 4.15 in the OCFS2 filesystem code path, specifically during DIRECT-mode read operations involving extent-tree access.

Is this easy to exploit remotely?

No. The vulnerability is locally exploitable, and the CVSS vector rates attack complexity as high; no network attack vector is indicated.

CVE-2017-18224: Race Condition

Affected Software

Remediation

Event History

Parent advisories

Frequently Asked Questions

Who can exploit this issue?

What is the likely impact of successful exploitation?

Which systems are affected?

Is this easy to exploit remotely?

Company

Resources

Contact

Frequently Asked Questions

Who can exploit this issue?

What is the likely impact of successful exploitation?

Which systems are affected?

Is this easy to exploit remotely?