#VU70508 Use-after-free in Linux kernel - CVE-2022-47946

Vulnerability identifier: #VU70508

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-2022-47946

CWE-ID: CWE-416

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 a use-after-free error within the io_sqpoll_wait_sq() function in fs/io_uring.c. A remote attacker can crash the kernel by forking a process and then quickly terminating it.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: before 5.10.155, 5.10.155

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v5.10.161&id=0f544353fec8e717d37724d95b92538e1de79e86
https://www.openwall.com/lists/oss-security/2022/12/22/2
https://www.openwall.com/lists/oss-security/2022/12/27/1

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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.