#VU53007 Out-of-bounds read in Linux kernel - CVE-2021-3506

Vulnerability identifier: #VU53007

Vulnerability risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-3506

CWE-ID: CWE-125

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition in fs/f2fs/node.c in the f2fs module in the Linux kernel. A local user can trigger out-of-bounds read error and read internal kernel information or crash the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.12, 5.12

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External links
https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg2520013.html
https://www.openwall.com/lists/oss-security/2021/03/28/2
https://bugzilla.redhat.com/show_bug.cgi?id=1944298
https://www.openwall.com/lists/oss-security/2021/05/08/1

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.