#VU90368 Out-of-bounds read in Linux kernel - CVE-2021-3444

Vulnerability identifier: #VU90368

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-2021-3444

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 execute arbitrary code.

The vulnerability exists due to an out-of-bounds read error within the fixup_bpf_calls() function in kernel/bpf/verifier.c. A local user can execute arbitrary code.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9b00f1b78809
https://www.openwall.com/lists/oss-security/2021/03/23/2
https://www.openwall.com/lists/oss-security/2021/03/23/2
https://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html
https://security.netapp.com/advisory/ntap-20210416-0006/
https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html
https://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html

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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.