grub2 up to 2.05 ext Filesystem Symlink heap-based overflow

Summaryinfo

A vulnerability identified as critical has been detected in grub2 up to 2.05. This impacts an unknown function of the component ext Filesystem Handler. The manipulation as part of Symlink leads to heap-based overflow. This vulnerability is referenced as CVE-2020-14311. The attack can only be performed from a local environment. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in grub2 up to 2.05. It has been rated as critical. This issue affects some unknown functionality of the component ext Filesystem Handler. The manipulation as part of a Symlink leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32_MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow.

The weakness was published 07/31/2020 as not defined bug report (Bugzilla). The advisory is shared at bugzilla.redhat.com. The identification of this vulnerability is CVE-2020-14311 since 06/17/2020. An attack has to be approached locally. The exploitation requires an enhanced level of successful authentication. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 236631 (Alibaba Cloud Linux 3 : 0026: grub2 (ALINUX3-SA-2021:0026)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.06 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (236631) and CERT Bund (WID-SEC-2022-0553). Similar entry is available at VDB-159244. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Ubuntu Linux
• IBM Security Guardium
• Open Source Grub
• Debian Linux
• Red Hat Enterprise Linux
• Microsoft Windows
• Cisco Identity Services Engine (ISE)
• SUSE Linux
• Cisco Router
• Oracle Linux
• HPE ProLiant
• Gentoo Linux
• Palo Alto Networks PAN-OS
• Avaya Aura Communication Manager
• Avaya Aura Session Manager
• Avaya Aura Application Enablement Services
• Avaya Aura System Manager
• Avaya Web License Manager
• Aruba ArubaOS

Productinfo

Name

• grub2

Version

• 2.05

License

• open-source

CPE 2.3info

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CPE 2.2info

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Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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