Analytical use of cookies
CVE-2025-21659: linux kernel vulnerability
CVE-2025-21659: high vulnerability affecting linux kernel. Check CVSS, KEV status, business impact and recommended administrator actions.
- CVSS
- 8.1 HIGH
- EPSS
- 7.75%
- Known exploited
- not in KEV
- Product
- linux kernel
What is known
In the Linux kernel, the following vulnerability has been resolved: netdev: prevent accessing NAPI instances from another namespace The NAPI IDs were not fully exposed to user space prior to the netlink API, so they were never namespaced. The netlink API must ensure that at the very least NAPI instance belongs to the same netns as the owner of the genl sock. napi_by_id() can become static now, but it needs to move because of dev_get_by_napi_id().
Business impact
Successful exploitation of CVE-2025-21659, a high vulnerability (CVSS 8.1) affecting linux kernel, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.
Recommended administrator action
Confirm whether linux kernel is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.