#VU106844 Buffer overflow in Linux kernel - CVE-2025-21927

Vulnerability identifier: #VU106844

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-2025-21927

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 escalate privileges on the system.

The vulnerability exists due to memory corruption within the nvme_tcp_queue_id() and nvme_tcp_recv_pdu() functions in drivers/nvme/host/tcp.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.12, 6.12.1, 6.12.2, 6.12.3, 6.12.4, 6.12.5, 6.12.6, 6.12.7, 6.12.8, 6.12.9, 6.12.10, 6.12.11, 6.12.12, 6.12.13, 6.12.14, 6.12.15, 6.12.16, 6.12.17, 6.12.18, 6.13, 6.13.1, 6.13.2, 6.13.3, 6.13.4, 6.13.5, 6.13.6

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External links
https://git.kernel.org/stable/c/22b06c89aa6b2d1ecb8aea72edfb9d53af8d5126
https://git.kernel.org/stable/c/9fbc953d6b38bc824392e01850f0aeee3b348722
https://git.kernel.org/stable/c/ad95bab0cd28ed77c2c0d0b6e76e03e031391064
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.12.19
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.13.7
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.14

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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.