#VU86575 Integer overflow in Linux kernel - CVE-2021-33631

Vulnerability identifier: #VU86575

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-33631

CWE-ID: CWE-190

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 escalate privileges on the system.

The vulnerability exists due to integer overflow when mounting a malicious filesystem. A local user can mount a specially crafted filesystem, trigger an integer overflow and execute arbitrary code.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://gitee.com/src-openeuler/kernel/pulls/1389
https://gitee.com/src-openeuler/kernel/pulls/1396
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5c099c4fdc438014d5893629e70a8ba934433ee8
https://www.openwall.com/lists/oss-security/2024/01/30/3
https://www.openwall.com/lists/oss-security/2024/01/30/4
https://www.openwall.com/lists/oss-security/2024/01/30/5
https://www.openwall.com/lists/oss-security/2024/01/30/9
https://www.openwall.com/lists/oss-security/2024/01/30/10
https://www.openwall.com/lists/oss-security/2024/01/31/3
https://www.openwall.com/lists/oss-security/2024/01/31/2
https://www.openwall.com/lists/oss-security/2024/02/02/6
https://www.openwall.com/lists/oss-security/2024/02/02/9
https://www.openwall.com/lists/oss-security/2024/02/03/1

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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.