CVE-2025-21962

In the Linux kernel, the following vulnerability has been resolved:

cifs: Fix integer overflow while processing closetimeo mount option

User-provided mount parameter closetimeo of type u32 is intended to have an upper limit, but before it is validated, the value is converted from seconds to jiffies which can lead to an integer overflow.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

This vulnerability is rated as having Moderate impact because exploitation requires local privileges to specify filesystem mount parameters, primarily resulting in a denial of service without compromising system confidentiality or integrity. In typical Red Hat Enterprise Linux deployments, the risk is constrained to environments where users or processes possess permissions to initiate SMB/CIFS network mounts with arbitrary parameters. Systems that do not actively mount remote CIFS shares remain unaffected during normal operation.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.