CVE-2021-39259: Buffer Overflow

Published Aug 30, 2021
·
Updated

A crafted NTFS image can trigger an out-of-bounds access, caused by an unsanitized attribute length in ntfsinodelookupbyname, in NTFS-3G < 2021.8.22.

Other sources

From https://www.openwall.com/lists/oss-security/2021/08/30/1:

Security vulnerabilities were identified in the open source NTFS-3G and NTFSPROGS software. These vulnerabilities were confirmed and resolved. To our knowledge, these vulnerabilities have not been exploited.

These vulnerabilities may allow an attacker using a maliciously crafted NTFS-formatted image file or external storage to potentially execute arbitrary privileged code, if the attacker has either local access and the ntfs-3g binary is setuid root, or if the attacker has physical access to an external port to a computer which is configured to run the ntfs-3g binary or one of the ntfsprogs tools when the external storage is plugged into the computer. These vulnerabilities result from incorrect validation of some of the NTFS metadata that could potentially cause buffer overflows, which could be exploited by an attacker. Common ways for attackers to gain physical access to a machine is through social engineering or an evil maid attack on an unattended computer.

We recommend installing and applying the update with the security fixes, and advise to follow security guidance and frameworks such as NIST for assessing and improving an organization’s abilities to prevent, detect, and respond to security threats and cyber attacks.

AFFECTED PRODUCTS: All previous versions of open source NTFS-3G and NTFSPROGS.

WORKAROUND: None

SOLUTION: Upgrade to 2021.8.22

PROJECT URL: https://github.com/tuxera/ntfs-3g

ADVISORY ID: NTFS3G-SA-2021-0001

ISSUE DATE: 2021-08-30

SEVERITY: Moderate

CVEs: CVE-2021-33285, CVE-2021-35269, CVE-2021-35268, CVE-2021-33289, CVE-2021-33286, CVE-2021-35266, CVE-2021-33287, CVE-2021-35267, CVE-2021-39251, CVE-2021-39252, CVE-2021-39253, CVE-2021-39254, CVE-2021-39255, CVE-2021-39256, CVE-2021-39257, CVE-2021-39258, CVE-2021-39259, CVE-2021-39260, CVE-2021-39261, CVE-2021-39262, CVE-2021-39263

CVSS SCORE: 3.9-6.7

ACKNOWLEDGMENT: Jeremy Galindo, Akshay Ajayan, Kyle Zeng and Fish Wang for reporting these vulnerabilities.

Red Hat

The ntfs3g package is susceptible to a heap overflow on crafted input. When processing an NTFS image, proper bounds checking was not enforced leading to this software flaw. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Affected Software

6 affected componentsFixes available
redhat/ntfs3g<2021.8.22
2021.8.22
tuxera NTFS-3G<2021.8.22
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Debian Debian Linux=11.0
debian/ntfs-3g
1:2017.3.23AR.3-4+deb11u41:2017.3.23AR.3-4+deb11u31:2022.10.3-1+deb12u21:2022.10.3-5

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/ntfs3g to a version that resolves this vulnerability.

    Fixed in 2021.8.22
  2. Upgrade

    Upgrade debian/ntfs-3g to a version that resolves this vulnerability.

    Fixed in 1:2017.3.23AR.3-4+deb11u4Fixed in 1:2017.3.23AR.3-4+deb11u3Fixed in 1:2022.10.3-1+deb12u2Fixed in 1:2022.10.3-5
  3. Upgrade

    Upgrade ntfs-3g to a version that resolves this vulnerability.

    Fixed in 2021.8.22
  4. Upgrade

    Upgrade ntfsprogs to a version that resolves this vulnerability.

    Fixed in 2021.8.22
  5. Compensating control

    Because exploitation could require local access with a setuid root ntfs-3g binary or physical access via external storage, ensure the system is not configured to run ntfs-3g/ntfsprogs on automatically attached external storage, and restrict physical/port access to prevent an attacker from plugging in a malicious NTFS image.

Event History

Aug 30, 2021
CVE Published
12:00 AM
Data Sourced
12:00 AM
RemedyDescriptionSeverityWeaknessAffected Software
Sep 7, 2021
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Data Sourced
via NVD·03:15 PM
DescriptionSeverityWeaknessAffected Software
Dec 2, 2025
Data Sourced
via Debian·09:38 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-39259?

CVE-2021-39259 has been rated as a high severity vulnerability due to the potential for out-of-bounds access in the NTFS-3G software.

2

How do I fix CVE-2021-39259?

To mitigate CVE-2021-39259, upgrade to NTFS-3G version 2021.8.22 or later.

3

What systems are affected by CVE-2021-39259?

CVE-2021-39259 affects NTFS-3G versions prior to 2021.8.22 on various Linux distributions including Debian and Red Hat.

4

What type of vulnerability is CVE-2021-39259?

CVE-2021-39259 is an out-of-bounds access vulnerability triggered by an unsanitized attribute length.

5

Is there any known exploitation of CVE-2021-39259?

There are no public reports of exploitation for CVE-2021-39259, but it is recommended to patch the vulnerability as a precaution.

Contact

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