#VU106842 Integer overflow in Linux kernel - CVE-2025-21963

Vulnerability identifier: #VU106842

Vulnerability risk: Low

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

CVE-ID: CVE-2025-21963

CWE-ID: CWE-190

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 integer overflow within the smb3_fs_context_parse_param() function in fs/smb/client/fs_context.c. A local user can execute arbitrary code.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 6.6 - 6.6.83

---

External links
https://git.kernel.org/stable/c/2809a79bc64964ce02e0c5f2d6bd39b9d09bdb3c
https://git.kernel.org/stable/c/39d086bb3558da9640ef335f97453e01d32578a1
https://git.kernel.org/stable/c/5b29891f91dfb8758baf1e2217bef4b16b2b165b
https://git.kernel.org/stable/c/6124cbf73e3dea7591857dd63b8ccece28952afd
https://git.kernel.org/stable/c/9e438d0410a4002d24f420f2c28897ba2dc0af64
https://mirrors.edge.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.84

---

Q & A

Can this vulnerability be exploited remotely?

Is there known malware, which exploits this vulnerability?