#VU90367 Out-of-bounds read in Linux kernel - CVE-2021-3489

Vulnerability identifier: #VU90367

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-2021-3489

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 __bpf_ringbuf_reserve() function in kernel/bpf/ringbuf.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://www.zerodayinitiative.com/advisories/ZDI-21-590/
https://ubuntu.com/security/notices/USN-4949-1
https://ubuntu.com/security/notices/USN-4950-1
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=4b81ccebaeee885ab1aa1438133f2991e3a2b6ea
https://www.openwall.com/lists/oss-security/2021/05/11/10
https://security.netapp.com/advisory/ntap-20210716-0004/

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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.