#VU107790 Buffer overflow in Linux kernel - CVE-2025-40364

Vulnerability identifier: #VU107790

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-2025-40364

CWE-ID: CWE-119

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 memory corruption within the io_alloc_async_data() and io_req_prep_async() functions in io_uring/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: 6.6, 6.6 rc1, 6.6 rc2, 6.6 rc3, 6.6 rc4, 6.6 rc5, 6.6 rc6, 6.6.1, 6.6.2, 6.6.3, 6.6.4, 6.6.5, 6.6.6, 6.6.7, 6.6.8, 6.6.9, 6.6.10, 6.6.11, 6.6.12, 6.6.13, 6.6.14, 6.6.15, 6.6.16, 6.6.17, 6.6.18, 6.6.19, 6.6.20, 6.6.21, 6.6.22, 6.6.23, 6.6.24, 6.6.25, 6.6.26, 6.6.27, 6.6.28, 6.6.29, 6.6.30, 6.6.31, 6.6.32, 6.6.33, 6.6.34, 6.6.35, 6.6.36, 6.6.37, 6.6.38, 6.6.39, 6.6.40, 6.6.41, 6.6.42, 6.6.43, 6.6.44, 6.6.45, 6.6.46, 6.6.47, 6.6.48, 6.6.49, 6.6.50, 6.6.51, 6.6.52, 6.6.53, 6.6.54, 6.6.55, 6.6.56, 6.6.57, 6.6.58, 6.6.59, 6.6.60, 6.6.61, 6.6.62, 6.6.63, 6.6.64, 6.6.65, 6.6.66, 6.6.67, 6.6.68, 6.6.69, 6.6.70, 6.6.71, 6.6.72, 6.6.73, 6.6.74, 6.6.75, 6.6.76, 6.6.77

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External links
https://git.kernel.org/stable/c/a1b17713b32c75a90132ea2f92b1257f3bbc20f3
https://git.kernel.org/stable/c/a94592ec30ff67dc36c424327f1e0a9ceeeb9bd3
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.78

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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.