Red Hat Security Advisory: kernel security update
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: can: j1939: implement NETDEV_UNREGISTER notification handler (CVE-2025-39925) * kernel: net/mlx5: fs, fix UAF in flow counter release (CVE-2025-39979) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
This Red Hat security advisory addresses two kernel vulnerabilities in Red Hat Enterprise Linux 9. CVE-2025-39925 involves the CAN J1939 subsystem where a NETDEV_UNREGISTER notification handler was missing and has now been implemented. CVE-2025-39979 is a use-after-free vulnerability in the mlx5 network driver affecting flow counter release. Both issues are fixed in the updated kernel packages provided by Red Hat. The advisory rates the impact as moderate and recommends applying the update and rebooting the system to activate the fixes.
Potential Impact
The vulnerabilities affect the Linux kernel, which is the core component of the operating system. The first vulnerability (CVE-2025-39925) relates to the CAN J1939 networking protocol stack, potentially impacting device network interface handling. The second vulnerability (CVE-2025-39979) is a use-after-free bug in the mlx5 network driver, which could lead to memory corruption or instability. The advisory classifies the overall impact as moderate. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 9 should apply the available kernel update as described in the Red Hat advisory RHSA-2025:22865 and reboot their systems to ensure the fixes take effect. No additional mitigation steps are indicated by the vendor.
Red Hat Security Advisory: kernel security update
Description
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: can: j1939: implement NETDEV_UNREGISTER notification handler (CVE-2025-39925) * kernel: net/mlx5: fs, fix UAF in flow counter release (CVE-2025-39979) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory addresses two kernel vulnerabilities in Red Hat Enterprise Linux 9. CVE-2025-39925 involves the CAN J1939 subsystem where a NETDEV_UNREGISTER notification handler was missing and has now been implemented. CVE-2025-39979 is a use-after-free vulnerability in the mlx5 network driver affecting flow counter release. Both issues are fixed in the updated kernel packages provided by Red Hat. The advisory rates the impact as moderate and recommends applying the update and rebooting the system to activate the fixes.
Potential Impact
The vulnerabilities affect the Linux kernel, which is the core component of the operating system. The first vulnerability (CVE-2025-39925) relates to the CAN J1939 networking protocol stack, potentially impacting device network interface handling. The second vulnerability (CVE-2025-39979) is a use-after-free bug in the mlx5 network driver, which could lead to memory corruption or instability. The advisory classifies the overall impact as moderate. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 9 should apply the available kernel update as described in the Red Hat advisory RHSA-2025:22865 and reboot their systems to ensure the fixes take effect. No additional mitigation steps are indicated by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:22865
- Cve Count
- 2
- Additional Cves
- ["CVE-2025-39979"]
Threat ID: 6a3da1d94853345fc182865d
Added to database: 06/25/2026, 21:47:05 UTC
Last enriched: 06/25/2026, 22:19:23 UTC
Last updated: 09/10/2026, 19:36:50 UTC
Views: 29
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