CVE-2021-39251: Buffer Overflow
A crafted NTFS image can cause a NULL pointer dereference in ntfsextentinodeopen 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
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/ntfs3gto a version that resolves this vulnerability.Fixed in 2021.8.22 - Upgrade
Upgrade
debian/ntfs-3gto 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 - Upgrade
Upgrade
ntfs-3gto a version that resolves this vulnerability.Fixed in 2021.8.22Patch NTFS3G-SA-2021-0001 - Upgrade
Upgrade
ntfsprogsto a version that resolves this vulnerability.Fixed in 2021.8.22Patch NTFS3G-SA-2021-0001
Event History
Frequently Asked Questions
What is the severity of CVE-2021-39251?
CVE-2021-39251 has a medium severity due to the potential for a NULL pointer dereference, which can lead to denial of service.
How do I fix CVE-2021-39251?
To fix CVE-2021-39251, update the ntfs-3g package to version 2021.8.22 or later.
Which software is affected by CVE-2021-39251?
CVE-2021-39251 affects ntfs-3g versions prior to 2021.8.22 on several distributions including Red Hat and Debian.
What type of vulnerability is CVE-2021-39251?
CVE-2021-39251 is a vulnerability that allows for a NULL pointer dereference in the ntfs_extent_inode_open function.
Is there a specific environment where CVE-2021-39251 is critical?
CVE-2021-39251 is particularly critical in environments using ntfs-3g on older versions as it may lead to application crashes.