#VU90811 Improper locking in Linux kernel - CVE-2021-28951

Vulnerability identifier: #VU90811

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-28951

CWE-ID: CWE-667

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 perform a denial of service (DoS) attack.

The vulnerability exists due to improper locking within the io_sq_offload_start(), io_disable_sqo_submit() and io_register_enable_rings() functions in fs/io_uring.c. A local user can perform a denial of service (DoS) attack.

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/stable/linux.git/commit/?id=3ebba796fa251d042be42b929a2d916ee5c34a49
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PTRNPQTZ4GVS46SZ4OBXY5YDOGVPSTGQ/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4VCKIOXCOZGXBEZMO5LGGV5MWCHO6FT3/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/T2S3I4SLRNRUQDOFYUS6IUAZMQNMPNLG/
https://security.netapp.com/advisory/ntap-20210430-0003/

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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.