#VU92408 Time-of-check time-of-use (toctou) race condition in Linux kernel - CVE-2023-1295

Vulnerability identifier: #VU92408

Vulnerability risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-1295

CWE-ID: CWE-367

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 time-of-check time-of-use (toctou) race condition error within the io_close_prep(), io_req_defer_prep(), io_issue_sqe() and io_grab_files() functions in fs/io_uring.c. A local user can execute arbitrary code.

Mitigation
Install update from vendor's repository.

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=b5dba59e0cf7e2cc4d3b3b1ac5fe81ddf21959eb
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=788d0824269bef539fe31a785b1517882eafed93
https://kernel.dance/788d0824269bef539fe31a785b1517882eafed93
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9eac1904d3364254d622bf2c771c4f85cd435fc2
https://kernel.dance/9eac1904d3364254d622bf2c771c4f85cd435fc2
https://security.netapp.com/advisory/ntap-20230731-0006/

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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.